JP7828052B2 - Method for producing fused polycyclic compounds having fused five-membered rings, indacene derivatives, and p-phenylenevinylene derivatives and methods for producing the same - Google Patents

Description

The present invention relates to a method for producing a fused polycyclic compound having five-membered rings, an indacene derivative, and a carbon-bridged p-phenylenevinylene derivative and a method for producing the same.

Indacene, a three-ring aromatic compound formed by the fusion of one six-membered ring and two five-membered rings, is useful as an intermediate for preparing various chemical products such as pharmaceuticals, as well as electronic materials such as light-emitting materials, electron transport materials, and hole transport materials, which are made from compounds with large π-electron systems. While the synthesis of fused polycyclic aromatic compounds is generally not easy, the present inventors have proposed synthesizing such indacene derivatives using a relatively simple procedure and further developing them to produce p-phenylenevinylene derivatives with large π-electron systems (see, for example, Patent Document 1).

The p-phenylenevinylene derivatives described in Cited Document 1 are compounds with a ladder-like structure bridged by carbon atoms, and are said to exhibit good luminescence efficiency and be useful as molecular wires. Such p-phenylenevinylene derivatives are said to be synthesized from indacene derivatives in which aryl groups such as phenyl groups are bonded to the carbon atoms that make up the five-membered ring, and Cited Document 1 introduces a procedure for synthesizing indacene derivatives in which the five-membered ring moiety is substituted with many phenyl groups.

On the other hand, when considering fused polycyclic compounds such as indacene derivatives as intermediates for synthesizing various chemical products, it is desirable for them to have many substituents, such as leaving groups, that serve as footholds for chemical reactions. However, while the synthetic procedure shown in Cited Document 1 is convenient for obtaining indacene derivatives that have many aryl groups, such as phenyl groups, on the five-membered ring, it is difficult to obtain indacene derivatives that have many alkyl groups or substituents that serve as footholds for chemical reactions on the five-membered ring.

JP 2011-32197 A

The present invention was made in light of the above circumstances, and aims to provide a method for producing a fused polycyclic compound with five-membered rings, which can yield intermediates equipped with many substituents useful as scaffolds for chemical reactions, as well as a novel p-phenylenevinylene derivative prepared by such a production method.

[0006] As a result of extensive research aimed at solving the above-mentioned problems, the present inventors have found that by treating a compound having a partial structure represented by the following general formula (1) with an acid such as a Lewis acid, a new five-membered ring is formed, converting it into a compound having a partial structure represented by the following general formula (2). The reaction mechanism is assumed to be as follows. Note that the following chemical reaction formula shows a compound ( _BF3 · _OEt2 ) in which diethyl ether is coordinated to boron trifluoride, a Lewis acid, as the acid, but the present invention is not limited thereto. Furthermore, the following reaction formula shows an example in which only one five-membered ring is formed. However, for example, if the aromatic ring represented by Ar has two substituents for forming a five-membered ring, two five-membered rings will be formed, and if the aromatic ring represented by Ar has three substituents for forming a five-membered ring, three five-membered rings will be formed. The new five-membered ring formed in this way has multiple halogen atoms (X), and therefore compounds containing this five-membered ring are useful as intermediates in the synthesis of various chemical products.

Specifically, the present invention provides the following:

The present invention provides a method for producing a fused polycyclic compound having fused five-membered rings, characterized by reacting a compound having a partial structure represented by the following general formula (1) with an acid to convert it into a compound having a partial structure represented by the following general formula (2):
(The double bond marked with * in the above general formula (1) may be cis- or trans-configured; in general formula (1), R ¹ and R ² are each independently a hydrogen atom, -CQ ₃ , or an aryl group which may have a substituent; or R ¹ and R ² combine to form a ring structure; each Q is each independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino group or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch ; each X is each independently a halogen atom; and the ring structure marked with the symbol Ar is an aromatic ring which may have a substituent. In the above general formula (2), R ¹ and R ² are each independently a hydrogen atom, -CQ ₃ , or an aryl group which may have a substituent; or R ^{R 1} and R ² combine to form a ring structure, each Q is independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch , each X is independently a halogen atom, and the ring structure designated by the symbol Ar is an aromatic ring which may have a substituent.

The acid is preferably a Lewis acid.

The above-mentioned Lewis acid is preferably boron trifluoride or a compound in which a Lewis base is bound to boron trifluoride to form a complex.

The present invention also relates to an indacene derivative represented by any one of the following general formulas (3A) to (3F).
(In the above general formulas (3A) to (3F), each R is independently a hydrogen atom, -CQ ₃ , or an aryl group which may have a substituent, or two Rs bonded to the same carbon atom combine to form a ring structure; each Q is independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch ; and each X is independently a halogen atom.)

The present invention also relates to a carbon-bridged p-phenylene vinylene derivative represented by the following general formula (4).
(In the above general formula (4), each R is _-CQ3 , and each Q is independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino group or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch .)

In the above general formula (4), each R is preferably an n-butyl group.

The present invention also provides a method for producing a carbon-bridged p-phenylenevinylene derivative, comprising: step i) reacting a compound represented by general formula (11) below with a first acid to obtain a compound represented by general formula (12): step ii) reacting an alkyllithium compound with the compound represented by general formula (12) below, and then reacting the compound represented by general formula (13) below to obtain a compound represented by general formula (14): step iii) coupling the compound represented by general formula (14) below with a 1,4-phenylenediboronic acid compound to obtain a compound represented by general formula (15): step iv) reacting the compound represented by general formula (15) below with a second acid to obtain a compound represented by general formula (16):
(In the above chemical reaction formula, each X is independently a halogen atom; each ^R1 and ^R2 is independently a hydrogen atom, _-CQ3 , or an aryl group which may have a substituent; or ^R1 and ^R2 combine to form a ring structure; each ^R3 and ^R4 is independently a hydrogen atom, _-CQ3 , or an aryl group which may have a substituent; or ^R3 and ^R4 combine to form a ring structure; and each Q is independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino group or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch .)

It is preferable that both the first acid and the second acid are Lewis acids.

The above-mentioned Lewis acid is preferably boron trifluoride or a compound in which a Lewis base is bound to boron trifluoride to form a complex.

It is preferable that all of R ¹ , R ² , R ³ and R ⁴ are n-butyl groups.

The present invention provides a method for producing a five-membered fused polycyclic compound that can yield intermediates equipped with many substituents useful as scaffolds for chemical reactions, as well as a novel p-phenylenevinylene derivative prepared by such a production method.

Below, we will explain one embodiment of the method for producing a fused polycyclic compound having five-membered rings of the present invention, one embodiment of an indacene derivative of the present invention, one embodiment of a carbon-bridged p-phenylenevinylene derivative of the present invention, and one embodiment of a method for producing a carbon-bridged p-phenylenevinylene of the present invention. Note that the present invention is not limited to the following embodiments and examples, and can be practiced with appropriate modifications within the scope of the present invention.

<Method for producing fused polycyclic compounds having five-membered rings>
First, one embodiment of the method for producing a fused polycyclic compound having five-membered rings bonded thereto according to the present invention will be described. The method for producing a fused polycyclic compound having five-membered rings bonded thereto according to the present invention is characterized in that a compound having a partial structure represented by the following general formula (1) is converted into a compound having a partial structure represented by the following general formula (2) by reacting it with an acid. By carrying out this production method, a five-membered ring fused to the aromatic ring represented by Ar in the following general formula (1) is added. This reaction can be carried out at room temperature and with good yield. Furthermore, since a halogen atom represented by X in the following general formula (2) is introduced into the fused ring, the compound represented by general formula (2) obtained by this reaction is useful as an intermediate for the synthesis of various chemical products. As such, according to the production method of the present invention, intermediates useful for the synthesis of various chemical products can be prepared with good yield through simple experimental procedures.

In the above general formula (1), the double bond portion is shown in trans form for convenience, but this double bond portion, i.e., the double bond marked with *, may be in either cis or trans form. As already explained, the compound represented by general formula (1) takes a cationic intermediate structure when the hydroxyl group contained in general formula (1) is abstracted by an acid, and at that time, an equilibrium state is reached in which the cis and trans forms alternate. When the cis form is taken, the carbon atoms bonded to ^R1 and ^R2 attack the aromatic ring, forming a five-membered ring. According to this reaction mechanism, the bond marked with * in general formula (1) may be in either cis or trans form. In the following chemical reaction formula _{, BF3.OEt2} is exemplified as the acid, but of course other acids may also be used.

In the general formula (1), ^R1 and ^R2 are each independently (a) a hydrogen atom, _-CQ3 , or an aryl group which may have a substituent, or (b) ^R1 and ^R2 combine to form a ring structure. In the case of (a), each Q is independently a hydrogen atom or a monovalent organic group. That is, when ^R1 or ^R2 is _-CQ3 , these have the structures _-CH3 , _-CH2Q , _CHQ2 , or _-CQ3 , and therefore have a carbon atom at the alkyl terminal, and the latter three have a hydrogen atom or a monovalent organic group at the end. Examples of such monovalent organic groups include alkyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkoxy groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylsulfanyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylamino groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, and alkylaryl groups. Examples of alkyl groups having 1 to 12 carbon atoms, which may have a branch, include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and 2-ethylhexyl. These alkyl groups may also have an aryl group, which may have a substituent, in the chain or at the end. Although alkyl groups having a heteroatom or aryl group in the chain cannot strictly be called alkyl groups, such groups are also referred to as alkyl groups in the present invention. In such cases, the number of carbon atoms contained in the aryl group is not included in the number of carbon atoms of the alkyl group. Furthermore, these alkyl groups may have various substituents. Examples of such substituents include a hydroxyl group, a nitro group, an amino group, a sulfo group, an aryl group, and an alkoxy group. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom. Among these, a hydrogen atom or an alkyl group having 1 to 12 carbon atoms is preferred as Q. Examples of the aryl group which may have the above-mentioned substituent include a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, a thienyl group, a furyl group, a pyridyl group, a pyrimidyl group, etc. In the case of (b), examples of the ring structure formed by combining ^R1 and ^R2 include an aliphatic ring or aromatic ring which may be substituted, such as a cyclopentane ring, a fluorene ring, a cyclohexane ring, an indene ring, a tetrahydrofuran ring, a pyran ring, a pyrrolidine ring, and a piperidine ring.

In the above general formula (1), each X is independently a halogen atom. Examples of such halogen atoms include chlorine atoms, bromine atoms, and iodine atoms, with bromine atoms being preferred.

In the above general formula (1), the ring structure marked with the symbol Ar is an aromatic ring which may have a substituent. Examples of such aromatic rings include a benzene ring, a naphthalene ring, an anthracene ring, a pyrene ring, a thiophene ring, a furan ring, a pyridine ring, and a pyrimidine ring. Among these, a benzene ring and a naphthalene ring are preferred. Note that the above general formula (1) is a partial structure of a compound, and Ar may have any substituent or may be a fused ring. For example, if Ar has another chain group shown in general formula (1), a compound with two fused five-membered rings is obtained, and if Ar has two more chain groups, a compound with three fused five-membered rings is obtained.

An example of a compound having the partial structure represented by the general formula (1) is as follows: In the following chemical formula, Me represents a methyl group, Bu represents an n-butyl group, Hex represents an n-hexyl group, and Ph represents a phenyl group.

By allowing an acid to act on a compound having the partial structure represented by the above general formula (1), a five-membered ring is formed, and a compound having the partial structure represented by the above general formula (2) is obtained. The acid may be a Brønsted acid or a Lewis acid. If the acid is, for example, a Brønsted acid, a proton will add to the hydroxyl group to form an -OH ₂ ⁺ group, which will then be released as a water molecule. If the acid is, for example, a Lewis acid, the Lewis acid will coordinate to the oxygen atom of the hydroxyl group, and then the coordinate will be released. In this way, either acid may be used, but among these, Lewis acids are preferred.

Examples of Lewis acids include boron trifluoride, boron trichloride, aluminum chloride, and titanium(IV) chloride. Among these Lewis acids, boron trifluoride is a preferred example, and from the standpoint of ease of handling, boron trifluoride bound to a Lewis base is even more preferred. Examples of such Lewis bases include, but are not limited to, diethyl ether.

When reacting an acid with a compound having a partial structure represented by general formula (1) to obtain a compound having a partial structure represented by general formula (2), the compound having the partial structure represented by general formula (1) is dissolved in a solvent and then reacted with an acid. In this case, the amount of acid added can be, for example, approximately 2 to 10 times the number of moles of the compound having the partial structure represented by general formula (1). After adding the acid, the reaction is carried out at room temperature for approximately 10 to 30 minutes to obtain a compound having a partial structure represented by general formula (2).

In the general formula (2), ^R1 and ^R2 are each independently (a) a hydrogen atom, _-CQ3 , or an aryl group which may have a substituent, or (b) ^R1 and ^R2 combine to form a ring structure. In the case of (a), each Q is independently a hydrogen atom or a monovalent organic group. That is, when ^R1 or ^R2 is _-CQ3 , they have a carbon atom at the alkyl terminal, and have a hydrogen atom or a monovalent organic group at the end of the carbon atom. Examples of such monovalent organic groups include alkyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkoxy groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylsulfanyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylamino groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, and alkylaryl groups. Examples of alkyl groups having 1 to 12 carbon atoms, which may have a branch, include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and 2-ethylhexyl. These alkyl groups may have an aryl group, which may have a substituent, in the chain or at the terminal. These alkyl groups may also have various substituents. Examples of such substituents include a hydroxyl group, a nitro group, an amino group, a sulfo group, an aryl group, and an alkoxy group. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom. Among these, Q is preferably a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and more preferably a hydrogen atom or an alkyl group having 3 to 12 carbon atoms. Examples of the aryl group, which may have the substituent, include a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, a thienyl group, a furyl group, a pyridyl group, and a pyrimidyl group. In the case of (b), examples of the ring structure formed by combining ^R1 and ^R2 include an optionally substituted aliphatic ring or aromatic ring, such as a cyclopentane ring, a fluorene ring, a cyclohexane ring, an indene ring, a tetrahydrofuran ring, a pyran ring, a pyrrolidine ring, and a piperidine ring.

In the above general formula (2), each X is independently a halogen atom. Examples of such halogen atoms include chlorine atoms, bromine atoms, and iodine atoms, with bromine atoms being preferred.

In the above general formula (2), the ring structure marked with the symbol Ar is an aromatic ring which may have a substituent. Examples of such aromatic rings include a benzene ring, a naphthalene ring, an anthracene ring, a pyrene ring, a thiophene ring, a furan ring, a pyridine ring, and a pyrimidine ring. Among these, a benzene ring and a naphthalene ring are preferred. Note that the above general formula (2) is a partial structure of a compound, and this Ar may have any substituent, or may be fused with a newly formed ring other than a five-membered ring.

Examples of compounds having the partial structure represented by general formula (2) above include the following. In the chemical formula below, Me represents a methyl group, Bu represents an n-butyl group, Hex represents an n-hexyl group, and Ph represents a phenyl group. In addition, in the chemical formula below, compounds 2a to 2p correspond to compounds synthesized by the manufacturing method of the present invention using compounds 1a to 1p shown in Compound Example 1 above as examples of compounds having the partial structure represented by general formula (1). For example, compound 2a below corresponds to a compound obtained by the manufacturing method of the present invention using compound 1a above as a raw material.

<Indacene derivatives>
The indacene derivatives represented by the following general formulas (3A) to (3F) also constitute part of the present invention. The indacene derivatives of the present invention are compounds having a three-ring structure and a skeleton in which five-membered rings are fused to both sides of a central benzene ring. The indacene derivatives of the present invention are preferably prepared by the method of the present invention for producing a fused polycyclic compound in which five-membered rings are fused, and contain many halogen atoms in the molecule, which serve as scaffolds for chemical reactions, and are therefore useful as synthetic intermediates for chemical products.

In the above general formulas (3A) to (3F), each R is independently (a) a hydrogen atom, -CQ ₃ , or an aryl group which may have a substituent, or (b) two Rs bonded to the same carbon atom combine to form a ring structure. In the case of (a), each Q is independently a hydrogen atom or a monovalent organic group. That is, when R is -CQ ₃ , it has a carbon atom at the alkyl terminal, and has a hydrogen atom or a monovalent organic group at its end. Examples of such monovalent organic groups include alkyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkoxy groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylsulfanyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylamino groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, and alkylaryl groups. Examples of alkyl groups having 1 to 12 carbon atoms, which may have a branch, include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and 2-ethylhexyl. These alkyl groups may have an aryl group, which may have a substituent, in the chain or at the terminal. These alkyl groups may also have various substituents. Examples of such substituents include a hydroxyl group, a nitro group, an amino group, a sulfo group, an aryl group, and an alkoxy group. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom. Among these, Q is preferably a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and more preferably a hydrogen atom or an alkyl group having 3 to 12 carbon atoms. Examples of the aryl group, which may have the substituent, include a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, a thienyl group, a furyl group, a pyridyl group, and a pyrimidyl group. In the case of (b), examples of the ring structure formed by combining two Rs bonded to the same carbon atom include an optionally substituted aliphatic ring and aromatic ring, such as a cyclopentane ring, a fluorene ring, a cyclohexane ring, an indene ring, a tetrahydrofuran ring, a pyran ring, a pyrrolidine ring, and a piperidine ring.

In the above general formulas (3A) to (3F), each X is independently a halogen atom. Examples of such halogen atoms include chlorine atoms, bromine atoms, and iodine atoms, with bromine atoms being preferred.

The compound represented by general formula (3A) and the compound represented by general formula (3B) are related in that one compound becomes the other compound when one five-membered ring in the compound flips upside down. These general formulas correspond to the above-mentioned compounds 2o and 2p, respectively, and these compounds are synthesized from the above-mentioned compounds 1o and 1p, respectively. In this way, in the method of producing a fused polycyclic compound having fused five-membered rings of the present invention, the compounds of the above-mentioned general formulas (3A) to (3F) can be produced by adjusting the position and number of the substituents in the substituted benzene starting material.

<Carbon-bridged p-phenylene vinylene derivative>
The present invention also includes a carbon-bridged p-phenylenevinylene derivative represented by the following general formula (4): The carbon-bridged p-phenylenevinylene derivative of the present invention is preferably prepared by the above-mentioned method of producing a fused polycyclic compound having fused five-membered rings of the present invention.

In the above general formula (4), each R is _-CQ3 , and each Q is independently a hydrogen atom or a monovalent organic group. That is, each R has a carbon atom as an alkyl terminal, and has a hydrogen atom or a monovalent organic group at its end. Examples of such monovalent organic groups include alkyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching along the way, alkoxy groups having 1 to 12 carbon atoms which may have a heteroatom or branching along the way, alkylsulfanyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching along the way, alkylamino groups having 1 to 12 carbon atoms which may have a heteroatom or branching along the way, and alkylaryl groups. Examples of alkyl groups having 1 to 12 carbon atoms which may have a branching along the way include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and 2-ethylhexyl groups. These alkyl groups may have an aryl group which may have a substituent in the chain or at the end. These alkyl groups may also have various substituents. Examples of such substituents include a hydroxyl group, a nitro group, an amino group, a sulfo group, an aryl group, and an alkoxy group. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom. Among these, R is preferably an n-butyl group, and it is more preferable that all R are n-butyl groups.

The key feature of the present invention is that in the above general formula (4), each R is bonded to the p-phenylenevinylene backbone via a carbon atom at the alkyl terminal, resulting in a substituted or unsubstituted alkyl group, which may be branched. In the above general formula (4), compounds in which each R is an aryl group are already known, and all have been reported to have good luminescence efficiency and molecular wire functionality (see, for example, J. Am. Chem. Soc. 2012, 134, 19254 and JP 2011-32197 A). However, the inventors' studies have revealed that carbon-bridged p-phenylenevinylene derivatives in which each R is an alkyl group having one or more carbon atoms exhibit larger molar absorption coefficients and radiative deactivation constants in fluorescence emission. A larger molar absorption coefficient means efficient absorption of excitation light, and a larger radiative deactivation constant in fluorescence emission means a shorter time from excitation to fluorescence radiative deactivation, enabling the emission of stronger fluorescence. For reference, Table 1 shows the molar absorption coefficient and radiative deactivation constant when each R in the above general formula (4) is Ar (p-octylphenyl group) and n-butyl group (present invention).

The carbon-bridged p-phenylene vinylene derivative of the present invention is prepared by a method for producing a carbon-bridged p-phenylene vinylene derivative, which also constitutes one aspect of the present invention. Next, the method for producing the carbon-bridged p-phenylene vinylene derivative of the present invention will be described.

<Method of producing p-phenylene vinylene derivative>
The method for producing a p-phenylene vinylene derivative of the present invention is an application of the method for producing a fused polycyclic compound having fused five-membered rings of the present invention, and is characterized by comprising: a step [i] of reacting a compound represented by the following general formula (11) with a first acid to obtain a compound represented by the following general formula (12), a step [ii] of reacting the compound represented by the following general formula (12) with an alkyllithium compound and then reacting it with a compound represented by the following general formula (13) to obtain a compound represented by the following general formula (14), a step [iii] of coupling the compound represented by the following general formula (14) with a 1,4-phenylenediboronic acid compound to obtain a compound represented by the following general formula (15), and a step [iv] of reacting the compound represented by the following general formula (15) with a second acid to obtain a compound represented by the following general formula (16). Each step will be described below.

(In the above chemical reaction formula, each X is independently a halogen atom; each ^R1 and ^R2 is independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an aryl group which may have a substituent; or ^R1 and ^R2 combine to form a ring structure; and each ^R3 and ^R4 is independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an aryl group which may have a substituent; or ^R3 and ^R4 combine to form a ring structure.)

[Step i]
Step i is a step of reacting a compound represented by the general formula (11) with a first acid to obtain a compound represented by the general formula (12). This chemical reaction is the same as the chemical reaction in the method of producing a fused polycyclic compound having fused five-membered rings of the present invention.

In general formulas (11) and (12), ^R1 and ^R2 are each independently (a) a hydrogen atom, _-CQ3 , or an aryl group which may have a substituent, or (b) ^R1 and ^R2 combine to form a ring structure. In the case of (a), each Q is independently a hydrogen atom or a monovalent organic group. That is, when ^R1 or ^R2 is _-CQ3 , they have a carbon atom at the alkyl terminal, and have a hydrogen atom or a monovalent organic group at the end of the carbon atom. Examples of such monovalent organic groups include alkyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkoxy groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylsulfanyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylamino groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, and alkylaryl groups. Examples of alkyl groups having 1 to 12 carbon atoms, which may have a branch, include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and 2-ethylhexyl. These alkyl groups may have an aryl group, which may have a substituent, in the chain or at the terminal. These alkyl groups may also have various substituents. Examples of such substituents include a hydroxyl group, a nitro group, an amino group, a sulfo group, an aryl group, and an alkoxy group. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom. Among these, Q is preferably a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and more preferably a hydrogen atom or an alkyl group having 3 to 12 carbon atoms. Examples of the aryl group, which may have the substituent, include a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, a thienyl group, a furyl group, a pyridyl group, and a pyrimidyl group. In the case of (b), examples of the ring structure formed by combining ^R1 and ^R2 include an optionally substituted aliphatic ring or aromatic ring, such as a cyclopentane ring, a fluorene ring, a cyclohexane ring, an indene ring, a tetrahydrofuran ring, a pyran ring, a pyrrolidine ring, and a piperidine ring. Among these, it is preferable that both ^R1 and ^R2 are n-butyl groups. ^R1 and ^R2 in general formula (11) are the same as ^R1 and ^R2 in general formula (12), respectively.

In the above general formulas (11) and (12), each X is independently a halogen atom. Examples of such halogen atoms include a chlorine atom, a bromine atom, and an iodine atom, with a bromine atom being preferred. Each X in general formula (11) is the same as the corresponding X in general formula (12).

By reacting a compound represented by the above general formula (11) with a first acid, a five-membered ring is formed, and a compound represented by the above general formula (12) is obtained. The first acid may be a Brønsted acid or a Lewis acid. This is as already explained in the method for producing a fused polycyclic compound of the present invention having a fused five-membered ring. Among these acids, Lewis acids are preferred as the first acid.

Examples of Lewis acids include boron trifluoride, boron trichloride, aluminum chloride, and titanium(IV) chloride. Among these Lewis acids, boron trifluoride is a preferred example, and from the standpoint of ease of handling, boron trifluoride bound to a Lewis base is even more preferred. Examples of such Lewis bases include, but are not limited to, diethyl ether.

When reacting a compound represented by general formula (11) with a first acid to obtain a compound represented by general formula (12), the compound represented by general formula (11) is dissolved in a solvent and then reacted with the first acid. In this case, the amount of the first acid added can be, for example, approximately 2 to 10 times the number of moles of the compound represented by general formula (11). After adding the acid, the reaction is carried out at room temperature for approximately 10 to 30 minutes to obtain the compound represented by general formula (12).

The compound represented by general formula (12) obtained in step i is subjected to appropriate purification and then to step ii.

[Step ii]
Step ii is a step of reacting a compound represented by the general formula (12) with an alkyllithium compound, and then reacting with a compound represented by the general formula (13) to obtain a compound represented by the general formula (14). That is, one X in the compound represented by the general formula (12) is lithiated to impart nucleophilicity, and then this is allowed to attack the carbonyl group of the compound represented by the general formula (13) to obtain a compound represented by the general formula (14).

R ¹ , R ² , and X in general formulas (12) and (14) are the same as those in general formula (11). R ¹ and R ² in general formula (14) are the same as R ¹ and R ² in general formula (12), respectively. X in general formula (14) is the same as the corresponding X in general formula (12).

The alkyllithium compound is a reagent used to lithiate X in the compound represented by general formula (12), and n-butyllithium is preferably used. The conditions for lithiation include, but are not limited to, dissolving the compound represented by general formula (12) in a solvent to form a solution, cooling it to -78°C, and adding the alkyllithium compound dropwise over approximately one hour with stirring. Anhydrous tetrahydrofuran is a preferred solvent for this purpose. The amount of alkyllithium compound added is preferably approximately equimolar to the amount of the compound represented by general formula (12). After the alkyllithium compound has been added dropwise, the lithiation is completed by stirring for approximately one hour while maintaining the temperature.

Next, the compound represented by general formula (13) is added dropwise to the solution after lithiation is complete. After the addition is complete, stirring is continued for about 30 minutes, and then the solution temperature is gradually returned to room temperature to quench the reaction. For example, an aqueous ammonium chloride solution can be added to the reaction solution to quench the reaction. Through these reactions, the compound represented by general formula (14) is obtained.

In general formulas (13) and (14), ^R3 and ^R4 are each independently (a) a hydrogen atom, _-CQ3 , or an aryl group which may have a substituent, or (b) ^R3 and ^R4 combine to form a ring structure. In the case of (a), each Q is independently a hydrogen atom or a monovalent organic group. That is, when ^R3 or ^R4 is _-CQ3 , they have a carbon atom at the alkyl terminal, and have a hydrogen atom or a monovalent organic group at the end of the carbon atom. Examples of such monovalent organic groups include alkyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkoxy groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylsulfanyl groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, alkylamino groups having 1 to 12 carbon atoms which may have a heteroatom or branching therein, and alkylaryl groups. Examples of alkyl groups having 1 to 12 carbon atoms, which may have a branch, include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and 2-ethylhexyl. These alkyl groups may have an aryl group, which may have a substituent, in the chain or at the terminal. These alkyl groups may also have various substituents. Examples of such substituents include a hydroxyl group, a nitro group, an amino group, a sulfo group, an aryl group, and an alkoxy group. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom. Among these, Q is preferably a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and more preferably a hydrogen atom or an alkyl group having 3 to 12 carbon atoms. Examples of the aryl group, which may have the substituent, include a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, a thienyl group, a furyl group, a pyridyl group, and a pyrimidyl group. In the case of (b), examples of the ring structure formed by combining ^R3 and ^R4 include an optionally substituted aliphatic ring or aromatic ring, such as a cyclopentane ring, a fluorene ring, a cyclohexane ring, an indene ring, a tetrahydrofuran ring, a pyran ring, a pyrrolidine ring, and a piperidine ring. Among these, it is preferable that both ^R3 and ^R4 are n-butyl groups. ^R3 and ^R4 in general formula (13) are the same as ^R3 and ^R4 in general formula (14), respectively.

The compound represented by general formula (14) obtained in step ii is subjected to appropriate purification and then to step iii.

[Step iii]
Step iii is a step in which a compound represented by the general formula (14) is subjected to a coupling reaction with a 1,4-phenylenediboronic acid compound to obtain a compound represented by the general formula (15). Through this reaction, two molecules of the compound represented by the general formula (14) are bonded together via a p-phenylene group to form a compound represented by the general formula (15). The coupling reaction referred to here is known as the Suzuki-Miyaura cross-coupling reaction.

R ¹ , R ² , R ³ and R ⁴ in the general formula (15) are the same as R ¹ , R ² , R ³ and R ⁴ in the general formula (14), and therefore the explanation thereof will be omitted here.

The 1,4-phenylenediboronic acid compound corresponds to the boronic acid compound used in the Suzuki-Miyaura cross-coupling reaction, and may be 1,4-phenylenediboronic acid itself, or a compound in which the two boronic acid moieties in 1,4-phenylenediboronic acid are protected. When using a compound in which the boronic acid moieties are protected, examples of protecting groups include pinacol esters of boronic acid, biscyclohexyldiol esters of boronic acid, diaminonaphthalenamides of boronic acid, and trifluoroborate salts.

Conditions for the coupling reaction of a compound represented by general formula (14) with a 1,4-phenylenediboronic acid compound can be the same as those typically used in the Suzuki-Miyaura cross-coupling reaction. One example of such conditions involves using 0.5 equivalents of 1,4-phenylenediboronic acid per equivalent of the compound represented by general formula (14), adding a palladium(0) catalyst and triphenylphosphine to a solvent containing aqueous potassium carbonate, and reacting at about 100°C for approximately 24 hours. In this case, the palladium(0) catalyst is preferably, but is not limited to, tris(dibenzylideneacetone)dipalladium(0), also known as Pd ₂ (dba) _3. The solvent is preferably, but is not limited to, dioxane.

The compound represented by general formula (15) obtained in step iii is subjected to step iv either directly or after appropriate purification.

[Step iv]
Step iv is a step of reacting a compound represented by the above general formula (15) with a second acid to obtain a compound represented by the above general formula (16).

R ¹ , R ² , R ³ and R ⁴ in the general formulae (15) and (16) are the same as R ¹ , R ² , R ³ and R ⁴ in the general formula (14), and therefore the explanation thereof will be omitted here.

The second acid may be a Bronsted acid or a Lewis acid. Among these acids, Lewis acids are preferred as the second acid.

Examples of Lewis acids include boron trifluoride, boron trichloride, aluminum chloride, and titanium(IV) chloride. Among these Lewis acids, boron trifluoride is a preferred example, and from the standpoint of ease of handling, boron trifluoride bound to a Lewis base is even more preferred. Examples of such Lewis bases include, but are not limited to, diethyl ether.

When reacting a compound represented by general formula (15) with a second acid to obtain a compound represented by general formula (16), the compound represented by general formula (15) is dissolved in a solvent and then reacted with the second acid. In this case, the amount of the second acid added can be, for example, approximately 2 to 10 times the number of moles of the compound represented by general formula (15). After adding the acid, the reaction is carried out at room temperature for approximately 10 to 30 minutes to obtain the compound represented by general formula (16).

The present invention will be explained in more detail below by showing examples, but the present invention is not limited to the following examples in any way.

First, we will select some of the compounds 0a-0p and describe the general procedure for synthesizing the starting compounds 0a-0p used to synthesize compounds 1a-1p shown in Compound Example 1 above. Compounds 0a-0p for which no synthesis procedure is described below can be synthesized using a procedure similar to the synthesis procedure below, or are commercially available. Compounds 0a-0p correspond to the starting compounds used to synthesize compounds 1a-1p in Compound Example 1 above, respectively. Similarly, compounds 1a-1p correspond to the starting compounds used to synthesize compounds 2a-2p in Compound Example 2 above, respectively.

Synthesis of 5-(p-tolylethynyl)nonan-5-ol (compound 0h)

1-Ethynyl-4-methylbenzene (290 mg, 2.50 mmol) was dissolved in 10 mL of dry tetrahydrofuran (THF), and the solution was cooled to 0°C. To this solution, n-butyllithium (1.57 mL as a 1.59 M hexane solution, 2.50 mmol) was added dropwise, and the mixture was stirred for 0.5 hours while maintaining the temperature. Next, 5-nonanone (349 mg, 2.45 mmol) was added dropwise to the reaction solution, and the mixture was stirred at 0°C for 3 hours. After completion of the reaction, water (10 mL) was added to the reaction solution to quench the reaction, and the mixture was extracted three times with 10 mL of methylene chloride. The combined organic phase was dried over magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:methylene chloride=1:1) to obtain compound 0h as a pale yellow oil (yield: 416 mg, 64%).
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.32-7.31 (m, 2H), 7.12-7.09 (m, 2H), 7.23-7.18 (m, 2H), 2.34 (s, 3H), 1.96 (s, 1 H), 1.78-1.66 (m, 4H), 1.58-1.51 (m, 4H), 1.42-1.34 (m, 4H), 0.96-0.92 (m, 6H).
¹³ C{ ¹ H}-NMR (150 MHz, CDCl ₃ ): δ (ppm) 138.1, 131.5, 128.9, 119.8, 91.5, 84.3, 71.6, 41.8, 26.5, 22.9, 21.4, 14.0.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₇ O ([M+H] ⁺ ): 259.2062, found: 259.2056.

5-(o-tolylethynyl)nonan-5-ol (compound 0i)

Compound 0i was obtained as a colorless oil (yield 81%) by the same procedure as above, except that different starting materials were used.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.39 (d, J = 7.8Hz, 1H), 7.23-7.18 (m, 2H), 7.15-7.11 (m, 1H), 2.43 (s, 3H), 1.98 (s , 1H), 1.80-1.69 (m, 4H), 1.61-1.53 (m, 5H), 1.44-1.34 (m, 4H), 0.91-0.96 (m, 7H).
¹³ C{ ¹ H}-NMR (150 MHz, CDCl ₃ ): δ (ppm) 139.9, 131.9, 129.2, 128.0, 125.4, 122.6, 96.3, 83.0, 71.7, 41.9, 26.5, 22.8, 20.6, 14.0.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₅ O ([MH] ⁺ ): 257.1905, found: 257.1895.

Synthesis of 5-[(4-methoxyphenyl)ethynyl]nonan-5-ol (Compound 0j)

1-Bromo-4-methoxybenzene (486.2 mg, 2.60 mmol), 5-ethynyl-5-nonanol (451.6 mg, 2.68 mmol), PdCl ₂ (PPh ₃ ) ₂ (78.9 mg, 0.11 mmol), and CuI (67.4 mg, 0.11 mmol) were dissolved in piperidine (2.7 mL). This solution was stirred at 80°C for 3 days, filtered, and the filtrate was concentrated. This was purified by silica gel column chromatography (hexane:methylene chloride=1:4) to give compound 0j as a brown oil (yield: 273.8 mg, 38%).
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.37-7.34 (m, 2H), 6.85-6.81 (m, 2H), 3.81 (s, 2H), 1.95 (s, 1H), 1.78-1 .68 (m, 4H), 1.58-1.51 (m, 6H), 1.42-1.34 (m, 4H), 0.95 (t, J=7.3Hz, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 159.5, 133.1, 115.0, 113.8, 90.8, 84.1, 71.6, 55.3, 41.9, 26.5, 22.9, 14.1
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₇ O ₂ ([M+H] ⁺ ): 275.2011, found: 257.2000.

5-[(4-bromophenyl)ethynyl]nonan-5-ol (compound 0k)

Compound 0k was obtained as a yellow oil (yield 27%) by the same procedure as above, except that different starting materials were used.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.45-7.42 (m, 2H), 7.29-7.26 (m, 2H), 1.95 (s, 1H), 1.78-1.66 (m, 4H), 1.57-1.49 (m, 4H), 1.42-1.33 (m, 4H), 0.93 (t, J=7.2Hz, 6H).
¹³ C{ ¹ H}-NMR (150 MHz, CDCl ₃ ): δ (ppm) 133.0, 131.4, 122.3, 121.8, 93.5, 83.1, 71.5, 41.7, 26.4, 22.8, 14.0.
HRMS (APCI+) m/z calcd for C ₁₇ H ₂₄ BrO ([M+H] ⁺ ): 323.1011, found: 323.1002.

5-{[4-(trifluoromethyl)phenyl]ethynylnonan-5-ol (compound 01)

Compound 01 was obtained as a pale yellow oil (yield 64%) by the same procedure as above, except that different starting materials were used.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.56 (d, J=8.2Hz, 2H), 7.52 (d, J=8.2Hz, 2H), 1.99 (s, 1H), 1.80-1.67 (m, 4H), 1.58-1.50 (m, 9H), 1.39 (m, 4H), 0.95 (t, J=7.3Hz, 6H).
¹³ C{ ¹ H}-NMR (150 MHz, CDCl ₃ ): δ (ppm) 131.9, 129.9 (q, ² J _CF = 33 Hz), 126.7, 125.2, 123.9 (q, ¹ J _CF =271Hz), 94.8, 83.0, 71.7, 41.7, 26.5, 22.9, 14.1.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₃ F ₃ O ([M] ⁺ ): 317.1701, found: 312.1691.

5-[(1,1'-biphenyl)-4-ylethynyl]nonan-5-ol (compound 0m)

Compound 0m was obtained as a pale yellow solid (yield 65%) by the same procedure as above, except that different starting materials were used.
M. p. :52-53℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.59 (dt, J = 7.0, 1.4 Hz, 2H), 7.55 (dd, J = 6.4, 1.8 Hz, 2H), 7.51-7.48 (m, 2H), 7.47-7.43 (m, 2H), 7.38-7.34 (m, 1H), 1.99 (s, 1H), 1.79-1.68 (m, 4H), 1.64-1.52 (m, 4H), 1.40 (m, 4H), 0.96 (t, J=7.1Hz, 6H).
¹³ C{ ¹ H}-NMR (150 MHz, CDCl ₃ ): δ (ppm) 140.9, 140.3, 132.1, 128.8, 127.6, 127.0, 126.9, 121.8, 92.9, 84.1, 71.7, 41.9, 26.5, 22.9, 14.1.
HRMS (APCI+) m/z calcd for C ₂₃ H ₂₈ O ([M] ⁺ ): 320.2140, found: 320.2123.

2-(3-butyl-3-hydroxynon-1-ynyl)naphthalene (compound 0n)

Compound 0n was obtained as a yellow oil (yield 71%) by the same procedure as above, except that different starting materials were used.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.94 (s, 1H), 7.82-7.76 (m, 3H), 7.49-7.45 (m, 3H), 2.01 (s, 1H), 1,79-1 .74 (m, 4H), 1.61-1.56 (m, 4H), 1.46-1.38 (m, 4H), 0.97 (t, J=7.2Hz, 3H).
¹³ C{ ¹ H}-NMR (150 MHz, CDCl ₃ ): δ (ppm) 132.8, 132.6, 131.3, 128.4, 127.8, 127.62, 127.56, 126.5, 126.4, 120.1, 92.6, 84.5, 71.6, 41.8, 26.5, 22.9, 14.0.
HRMS (APCI+) m/z calcd for C ₂₁ H ₂₆ O ([M] ⁺ ): 294.1984, found: 294.1984.

1,3-bis(3-butyl-3-hydroxynon-1-ynyl)benzene (compound 0p)

Compound 0p was obtained as a white solid (yield 56%) by the same procedure as above, except that different starting materials were used.
M. p. :115-117℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.47 (brs, 1H), 7.35 (dd, J=8.4, 1.2Hz, 2H), 7.25 (t, J=8.4Hz, 1H), 1.96 (s, 2H), 1 .78-1.67 (m, 8H), 1.58-1.50 (m, 16H), 1.43-1.34 (m, 8H), 0.95 (t, J=7.6Hz, 12H).
¹³ C{ ¹ H}-NMR (150 MHz, CDCl ₃ ): δ (ppm) 134.7, 131.3, 128.3, 123.1, 92.9, 83.4, 71.6, 41.8, 26.5, 22.9, 14.1.
HRMS (APCI+) m/z calcd for C ₁₂ H ₁₃ Br ₂ ([M] ⁺ ): 410.3185, found: 410.3175.

Next, we will select some of compounds 1a-1p and describe the general procedure for synthesizing starting compounds 1a-1p for synthesizing compounds 2a-2p shown in Compound Example 2 above. Compounds 1a-1p for which no synthesis procedure is described below can be synthesized using a procedure similar to the synthesis procedure below. Furthermore, as noted above, compounds 1a-1p correspond to the starting compounds used to synthesize compounds 2a-2p in Compound Example 2 above, respectively.

Synthesis of (E)-3,4-dibromo-2-methyl-4-phenylbut-3-en-2-ol (Compound 1a)

N-Bromosuccinimide (NBS; 698 mg, 3.92 mmol) and tetrabutylammonium bromide (TBAB; 1.27 g, 3.93 mmol) were added to a methylene chloride solution (0.25 mL) of 2-methyl-4-phenylbut-3-yn-2-ol (209 mg, 1.30 mmol), and the mixture was stirred at room temperature for 72 hours. A saturated aqueous solution of sodium thiosulfate was added to the reaction solution, and the mixture was extracted three times with 10 mL of methylene chloride. The combined organic phase was dried over magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:methylene chloride=1:1) to give compound 1a as a white solid (yield: 205 mg, 49%).
M. p. :174-175℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.41-7.36 (m, 2H), 7.33-7.27 (m, 3H), 1.74 (s, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 143.6, 130.7, 128.6, 128.6, 128.5, 113.9, 76.0, 30.0.
HRMS (APCI+) m/z calcd for C ₁₁ H ₁₁ Br ₂ ([M-OH] ⁺ ): 300.9228, found: 300.9220.

(E)-1,2-Dibromo-3-methyl-1-phenylpent-1-en-3-ol (Compound 1b)

Compound 1b was obtained as a white solid (yield 82%) by the same procedure as above, except that compound 0b was used as the starting material.
M. p. :54.5-56℃. ¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.40-7.37 (m, 2H), 7.33-7.29 (m, 1H), 7.26 (dd, J=4.7, 2.7Hz, 2H), 2.98 (s, 1 H), 2.28-2.19 (m, 1H), 2.00-1.91 (m, 1H), 1.71 (s, 3H), 1.07 (t, J=7.3Hz, 3H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 143.8, 130.3, 128.5, 128.4, 128.2, 113.9, 78.4, 34.2, 28.0, 8.3
HRMS (APCI+) m/z calcd for C ₁₂ H ₁₃ Br ₂ ([M-OH] ⁺ ): 314.9384, found: 314.9374.

(E)-1,2-Dibromo-2-phenylhept-1-en-3-ol (Compound 1c)

Compound 1c was obtained as a white solid (yield 42%) by the same procedure as above, except that compound 0c was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.40-7.36 (m, 2H), 7.32-7.28 (m, 1H), 7.25-7.22 (m, 2H), 2.85 (s, 1H), 2.31 -2.23 (m, 2H), 1.80-1.71 (m, 2H), 1.60-1.34 (m, 10H), 0.95 (q, J=6.9Hz, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 144.2, 129.9, 128.5, 128.3, 128.1, 114.0, 80.6, 40.2, 25.5, 23.0, 14.1
HRMS (APCI+) m/z calcd for C ₁₇ H ₂₄ Br ₂ O ([MH] ⁺ ): 401.0116, found: 401.0101.

(E)-1,2-Dibromo-1-phenylnon-1-en-3-ol (Compound 1d)

Compound 1d was obtained as a colorless oil (yield 42%) by the same procedure as above, except that compound 0d was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.41-7.32 (m, 5H), 4.97 (q, J = 7.2Hz, 1H), 2.00-1.99 (m, 1H), 1.79-1.69 (m, 2H), 1.53-1.31 (m, 8H), 0.91 (t, J = 7.1Hz, 3H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 140.4, 129.0, 128.5, 128.1, 117.0, 74.0, 36.1, 31.8, 29.2, 25.1, 22.7, 14.2.
HRMS (APCI+) m/z calcd for C ₁₅ H ₁₉ Br ₂ ([M-OH] ⁺ ): 356.9854, found: 356.9838.

(E)-2,3-Dibromo-1,1,3-triphenylprop-2-en-1-ol (Compound 1e)

Compound 1e was obtained as a white solid (yield 76%) by the same procedure as above, except that compound 0e was used as the starting material.
M. p. : 103℃ (decomposition).
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.52-7.48 (m, 4H), 7.42-7.31 (m, 11H), 4.20 (s, 1H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 144.4, 143.4, 130.4, 129.1, 128.8, 128.7, 128.4, 128.2, 128.1, 119.1, 84.5
HRMS (APCI+) m/z calcd for C ₂₁ H ₁₅ Br ₂ ([M-OH] ⁺ ): 424.9541, found: 424.9532.

(E)-9-(1,2-dibromo-2-phenylvinyl)-9H-fluoren-9-ol (Compound 1g)

Compound 1g was obtained as a white solid (yield 76%) by the same procedure as above, except that 0g of compound was used as the starting material.
M. p. :141-143℃ (sublimation).
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.67-7.65 (m, 4H), 7.45-7.41 (m, 2H), 7.38-7.34 (m, 4H), 7.26-7.31 (m, 3H), 3.24 (s, 1H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 147.3, 143.1, 140.7, 129.7, 128.6, 128.5, 128.4, 123.6, 120.3, 116.3.
HRMS (APCI+) m/z calcd for C ₂₁ H ₁₅ Br ₂ O ([M+H] ⁺ ): 440.9484, found: 440.9472.

(E)-1,2-Dibromo-3-butyl-1-(p-tolyl)hept-1-en-3-ol (Compound 1h)

Compound 1h was obtained as a white solid (yield 92%) by the same procedure as above, except that compound 0h was used as the starting material.
M. p. :41-42℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.20-7.18 (m, 2H), 7.15-7.13 (m, 2H), 2.88 (s, 1H), 2.37 (s, 3H), 2.30-2 .22 (m, 2H), 1.79-1.71 (m, 2H), 1.60-1.34 (m, 8H), 0.96 (t, J=7.1Hz, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 141.6, 138.4, 129.8, 129.3, 128.2, 114.4, 80.7, 40.4, 25.7, 23.1, 21.5, 14.2.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₅ Br ₂ ([M-OH] ⁺ ): 399.0323, found: 399.0309.

(E)-1,2-dibromo-3-butyl-1-(o-tolyl)hept-1-en-3-ol (compound 1i)

Compound 1i was obtained as a colorless oil (yield 90%) by the same procedure as above, except that compound 0i was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.25-7.20 (m, 3H), 7.10-7.07 (m, 1H), 2.87 (s, 1H), 2.37-2.23 (m, 5H), 1.79-1.72 (m, 2H), 1.62-1.33 (m, 8H), 0.96 (t, J=7.1Hz, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 143.4, 134.4, 130.7, 130.4, 128.6, 127.9, 126.3, 114.0, 80.7, 40.4, 25.7, 25.6, 23.0, 19.1, 14.1.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₅ Br ₂ ([M-OH] ⁺ ): 399.0323, found: 399.0303.

(E)-1,2-dibromo-3-butyl-1-(p-methoxyphenyl)hept-1-en-3-ol (compound 1j)

Compound 1j was obtained as a colorless oil (yield 39%) by the same procedure as above, except that compound 0j was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.24-7.18 (m, 2H), 6.91-6.88 (m, 2H), 3.83 (s, 3H), 2.90 (s, 1H), 2.29-2 .22 (m, 2H), 1.79-1.71 (m, 2H), 1.53-1.34 (m, 8H), 0.96 (t, J=7.3Hz, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 159.3, 136.7, 129.8, 129.7, 114.3, 113.8, 80.6, 55.3, 40.2, 25.6, 23.0, 14.1.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₇ Br ₂ O ₂ ([M+H] ⁺ ): 433.0372, found: 433.0370.

(E)-1,2-dibromo-3-butyl-1-(p-bromophenyl)hept-1-en-3-ol (compound 1k)

Compound 1k was obtained as a white solid (yield 94%) by the same procedure as above, except that compound 0k was used as the starting material.
M. p. :47-48℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.53-7.49 (m, 2H), 7.13-7.09 (m, 2H), 2.78 (s, 1H), 2.28-2.20 (m, 2H), 1. 79-1.71 (m, 2H), 1.58-1.49 (m, 2H), 1.46-1.34 (m, 6H), 0.98-0.94 (m, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 143.0, 131.8, 130.7, 129.9, 122.4, 112.7, 80.7, 40.2, 25.5, 23.0, 14.0.
HRMS (APCI+) m/z calcd for C ₁₇ H ₂₂ Br ₃ O ([M-OH] ⁺ ): 462.9272, found: 462.9250.

(E)-1,2-Dibromo-3-butyl-1-(p-trifluoromethylphenyl)hept-1-en-3-ol (Compound 11)

Compound 11 was obtained as a colorless oil (yield 94%) by the same procedure as above, except that compound 01 was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.65 (d, J=7.6Hz, 2H), 7.36 (d, J=7.6Hz, 2H), 2.75 (s, 1H), 2.29-2.22 (m, 2H), 1 .81-1.73 (m, 2H), 1.60-1.51 (m, 2H), 1.48-1.35 (m, 6H), 0.97 (t, J=7.3Hz, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 147.5, 131.2, 130.3 (q, ² J _CF = 32 Hz), 128.8, 125.8, 123.8 (q, ¹ J _CF =271Hz), 112.2, 80.9, 40.3, 25.6, 23.0, 14.1
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₂ Br ₂ F ₃ ([M-OH] ⁺ ): 470.0040, found: 470.0027.

4-[(E)-1,2-dibromo-3-butyl-3-hydroxyhept-1-enyl][1,1'-biphenyl] (Compound 1m)

Compound 1m was obtained as a white solid (yield 66%) by the same procedure as above, except that compound 0m was used as the raw material.
M. p. :46-47℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.62-7.60 (m, 4H), 7.47-7.43 (m, 2H), 7.38-7.32 (m, 3H), 2.87 (s, 1H), 2.32 -2.24 (m, 2H), 1.81-1.74 (m, 2H), 1.62-1.36 (m, 8H), 0.98 (t, J=7.1Hz, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 143.0, 141.1, 140.3, 130.1, 128.8, 128.7, 127.6, 127.2, 127.1, 113.8, 80.7, 40.2, 25.6, 23.0, 14.1.
HRMS (APCI+) m/z calcd for C ₂₃ H ₂₉ Br ₂ O ([M+H] ⁺ ): 479.0580, found: 479.0561.

2-[(E)-1,2-dibromo-3-butyl-3-hydroxyhept-1-enyl]naphthalene (Compound 1n)

Compound 1n was obtained as a pale yellow oil in the same manner as above, except that compound 0n was used as the starting material (yield: 87%).
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.87-7.84 (m, 3H), 7.72 (s, 1H), 7.53-7.49 (m, 2H), 7.35 (dd, J=8.7, 1.8Hz, 1H), 2.89 ( s, 1H), 2.34-2.26 (m, 2H), 1.83-1.76 (m, 2H), 1.64-1.37 (m, 8H), 0.99 (t, J=7.1Hz, 6H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 141.4, 133.0, 132.8, 130.3, 128.4, 128.3, 127.7, 127.4, 126.7, 126.4, 125.9, 114.1, 80.7, 40.3, 25.6, 23.0, 14.2.
HRMS (APCI+) m/z calcd for C ₂₁ H ₂₆ Br ₂ O ([M] ⁺ ): 452.0350, found: 452.0350.

1,4-bis[(E)-1,2-dibromo-3-butyl-3-hydroxyhept-1-enyl]benzene (compound 1o)

Compound 1o was obtained as a yellow viscous oil in a 90% yield by the same procedure as above, except that compound 0o was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.26 (s, 4H), 2.83 (s, 1H), 2.29-2.23 (m, 4H), 1.80-1.72 (m, 4H), 1.60-1.34 (m, 24H), 0.96 (t, J=7.1Hz, 12H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 143.8, 130.4, 128.5, 113.2, 80.7, 40.2, 25.6, 23.0, 14.1.
HRMS (APCI+) m/z calcd for C ₂₈ H ₄₁ Br ₄ O ([MH] ⁺ ): 725.9891, found: 708.9877.

1,3-bis[(E)-1,2-dibromo-3-butyl-3-hydroxyhept-1-enyl]benzene (compound 1p)

Compound 1p was obtained as a colorless oil (yield 71%) by the same procedure as above, except that compound 0p was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.41 (t, J=7.6Hz, 1H), 7.19 (dd, J=7.6, 1.6Hz, 2H), 7.10 (t, J=1.6Hz, 1H), 2.83 (s, 2H), 2.29-2.18 (m, 4H), 1.81-1.74 (m, 4H), 1.60-1.35 (m, 16H), 0.99-0.91 (m, 12H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 144.3, 130.6, 128.8, 128.5, 128.1, 113.1, 80.7, 40.2, 25.5, 23.0, 14.1.
HRMS (APCI+) m/z calcd for C ₂₈ H ₄₂ Br ₄ O ₂ ([M-OH] ⁺ ): 705.9891, found: 708.9862.

Next, we will select some of compounds 2a-2p and describe the general procedure for synthesizing compounds 2a-2p shown in Compound Example 2 above using starting compounds 1a-1p. Compounds 2a-2p for which no synthesis procedure is described below can be synthesized using a procedure similar to the synthesis procedure below. Furthermore, as noted above, compounds 1a-1p correspond to the starting compounds used to synthesize compounds 2a-2p in Compound Example 2 above, respectively.

Synthesis of 2,3-dibromo-1,1-dimethyl-1H-indene (compound 2a)

To a chloroform solution (5.7 mL) of compound 1a (183 mg, 0.57 mmol) _{, BF3.OEt2} (245 mg, 1.72 mmol) was added, and the mixture was stirred at room temperature for 15 minutes. An excess amount of methanol was added to the reaction mixture to quench the reaction, and the mixture was then purified by silica gel column chromatography (hexane:methylene chloride = 1:1) to obtain compound 2a as a colorless oil (yield 164 mg, 95%). The spectral data of compound 2a were in good agreement with those reported previously (Knorr, R. et. al, J. Org. Chem. 2016, 12, 1178-1184).

2,3-dibromo-1-ethyl-1-methyl-1H-indene (compound 2b)

Compound 2b was obtained as a colorless oil (yield 92%) by the same procedure as above, except that compound 1b was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.37-7.34 (m, 1H), 7.33-7.28 (m, 1H), 7.27-7.25 (m, 2H), 1.94-1.81 (m, 2H), 1.30 (s, 3H), 0.36 (t, J=7.6Hz, 3H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 148.0, 141.1, 137.1, 127.2, 126.3, 121.4, 120.6, 120.1, 56.9, 30.6, 23.8, 8.0.
HRMS (APCI+) m/z calcd for C ₁₂ H ₁₂ Br ₂ ([M] ⁺ ): 313.9306, found: 313.9300.

2,3-dibromo-1,1-dibutyl-1H-indene (compound 2c)

Compound 2c was obtained as a colorless oil (yield 82%) by the same procedure as above, except that compound 1c was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.35-7.33 (m, 1H), 7.30 (td, J=7.0, 1.5Hz, 1H), 7.28-7.24 (m, 1H), 7.23-7.21 (m, 1H), 1.86-1.75 (m, 4H), 1.19-1.04 (m, 4H), 0.83-0.71 (m, 8H), 0.51-0.39 (m, 2H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 146.9, 142.0, 136.2, 127.0, 126.2, 121.3, 120.7, 119.9, 60.5, 37.5, 25.1, 22.7, 13.8.
HRMS (APCI+) m/z calcd for C ₁₇ H ₂₂ Br ₂ ([M] ⁺ ): 384.0088, found: 384.0076.

2,3-dibromo-1-hexyl-1H-indene (compound 2d)

Compound 2d was obtained as a colorless oil (yield 90%) by the same procedure as above, except that compound 1d was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.39-7.31 (m, 3H), 7.27 (td, J=7.2, 1.5Hz, 1H), 3.66-3.60 (m, 1H), 2.12 -2.03 (m, 1H), 1.96-1.88 (m, 1H), 1.29-1.04 (m, 7H), 0.97-0.84 (m, 4H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 144.4, 142.2, 131.1, 127.3, 126.2, 122.7, 122.0, 120.2, 54.0, 31.6, 30.2, 29.8, 29.5, 24.0, 22.7, 14.1.
HRMS (APCI+) m/z calcd for C ₁₅ H ₁₈ Br ₂ ([M] ⁺ ): 355.9770, found: 355.9764.

2',3'-dibromospiro[fluorene-9,1'-indene] (compound 2g)

Compound 2g was obtained as a white solid (yield 98%) by the same procedure as above, except that compound 1g was used as the starting material.
M. p. :155-156℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.80 (d, J=7.2Hz, 2H), 7.48 (d, J=7.7Hz, 1H), 7.40 (dd, J=7.9, 7.0Hz, 2H), 7.35-7.31 (m, 1H), 7.19 (dd, J=7.9, 7.0Hz, 2H), 7.09-7.05 (m, 1H), 6.86 (d, J=7.2Hz, 2H), 6.64 (d, J=7.7Hz, 1H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 145.9, 143.4, 142.3, 142.0, 131.9, 128.6, 128.0, 127.9, 127.3, 124.1, 123.6, 122.7, 120.3, 77.2, 70.6.
HRMS (APCI+) m/z calcd for C ₂₁ H ₁₂ Br ₂ ([M] ⁺ ): 421.9300, found: 421.9294.

2,3-dibromo-1,1-dibutyl-6-methyl-1H-indene (compound 2h)

Compound 2h was obtained as a white solid (yield 99%) by the same procedure as above, except that compound 1h was used as the starting material.
M. p. :35.5-36.5℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.21 (d, J=7.8Hz, 1H), 7.10 (d, J=7.8Hz, 1H), 7.02 (s, 1H), 2.40 (s, 3H), 1. 81-1.74 (m, 4H), 1.18-1.06 (m, 4H), 0.84-0.71 (m, 8H), 0.41-0.52 (m, 2H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 147.0, 139.5, 136.2, 134.8, 127.7, 122.2, 120.6, 119.6, 60.3, 37.6, 25.1, 22.8, 21.7, 13.8.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₄ Br ₂ ([M] ⁺ ): 398.0239, found: 398.0229.

2,3-dibromo-1,1-dibutyl-5-methyl-1H-indene (compound 2i)

Compound 2i was obtained as a white solid (yield 72%) by the same procedure as above, except that compound 1i was used as the starting material.
M. p. :44.5-46℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.13 (dd, J=7.0, 7.0Hz, 1H), 7.07 (d, J=7.0Hz, 1H), 7.01 (d, J=7.0Hz, 1H), 2.72 (s, 3 H), 1.83-1.71 (m, 4H), 1.19-1.05 (m, 4H), 0.81-0.70 (m, 8H), 0.50-0.39 (m, 2H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 147.8, 138.3, 137.5, 131.0, 130.1, 125.9, 119.9, 119.4, 59.6, 37.9, 25.0, 22.7, 19.9, 13.8.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₄ Br ₂ ([M] ⁺ ): 398.0239, found: 398.0238.

2,3-Dibromo-1,1-dibutyl-6-methoxy-1H-indene (compound 2j)

Compound 2j was obtained as a colorless oil (yield 95%) by the same procedure as above, except that compound 1j was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.23 (d, J=8.2Hz, 1H), 6.83 (dd, J=8.2, 2.3Hz, 1H), 6.80 (d, J=2.3Hz, 1H), 3.85 (s , 3H), 1.83-1.70 (m, 4H), 1.20-1.04 (m, 4H), 0.86-0.69 (m, 8H), 0.54-0.40 (m, 2H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 159.0, 148.6, 135.2, 133.0, 120.5, 120.1, 111.4, 108.7, 60.4, 55.6, 37.7, 25.1, 22.7, 13.8.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₄ Br ₂ O ₂ ([M] ⁺ ): 414.0194, found: 414.0191.

2,3,6-tribromo-1,1-dibutyl-1H-indene (compound 2k)

Compound 2k was obtained as a white solid (yield 68%) by the same procedure as above, except that compound 1k was used as the starting material.
M. p. :43-44℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.45 (dd, J=7.8, 1.6Hz, 1H), 7.36 (d, J=1.6Hz, 1H), 7.19 (d, J=7.8Hz, 1H), 1 .83-1.72 (m, 4H), 1.21-1.05 (m, 4H), 0.83-0.66 (m, 8H), 0.51-0.38 (m, 2H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 149.0, 141.1, 136.7, 130.4, 124.7, 121.4, 120.9, 120.1, 61.0, 37.5, 25.1, 22.8, 13.9.
HRMS (APCI+) m/z calcd for C ₁₇ H ₂₁ Br ₃ ([M] ⁺ ): 461.9188, found: 461.9197.

2,3-Dibromo-1,1-dibutyl-6-(trifluoromethyl)-1H-indene (Compound 21)

Compound 2l was obtained as a white solid (yield 30%) by the same procedure as above, except that compound 1l was used as the starting material.
M. p. :66.5-68℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.59 (d.
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 147.4, 145.3, 139.6, 128.3 (q, ² J _CF = 32 Hz), 124.7, 124.4 (q, ¹ J _CF =276Hz), 120.2, 120.0, 118.0, 61.1, 37.3, 25.0, 22.6, 13.7.
HRMS (APCI+) m/z calcd for C ₁₈ H ₂₁ Br ₂ F ₃ ([M]+): 451.9962, found: 451.9942.

2,3-Dibromo-1,1-dibutyl-6-phenyl-1H-indene (Compound 2m)

Compound 2m was obtained as a colorless viscous liquid (yield 63%) by the same procedure as above, except that compound 1m was used as the starting material.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.65-7.63 (m, 2H), 7.55 (dd, J=4.0, 1.6Hz, 1H), 7.49-46 (m, 3H), 7.41-7.34 (m, 2 H), 1.91-1.79 (m, 4H), 1.23-1.07 (m, 4H), 0.90-0.73 (m, 8H), 0.61-0.48 (m, 2H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 147.5, 141.3, 141.1, 139.4, 136.3, 128.8, 127.3, 127.2, 126.1, 120.5, 120.2, 120.1, 60.7, 37.6, 25.1, 22.7, 13.8.
HRMS (APCI+) m/z calcd for C ₂₃ H ₂₆ Br ₂ ([M] ⁺ ): 460.0396, found: 460.0384.

2,3-Dibromo-1,1-dibutyl-1H-cyclopenta[a]naphthalene (compound 2n)

Compound 2n was obtained as a white solid (yield 92%) by the same procedure as above, except that compound 1n was used as the starting material.
M. p. :72-73.5℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 8.07 (d, J=8.4Hz, 1H), 7.95 (d, J=8.8Hz, 1H), 7.86 (d, J=8.4Hz, 1H), 7.61-7.47 (m, 3H), 2.2 9-2.22 (m, 2H), 2.09-2.02 (m, 2H), 1.14-0.97 (m, 4H), 0.70-0.59 (m, 8H), 0.30-0.19 (m, 2H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 141.4, 139.9, 136.7, 132.5, 129.7, 128.7, 128.5, 126.6, 125.0, 122.7, 120.7, 118.7, 62.5, 37.8, 25.0, 22.6, 13.7.
HRMS (APCI+) m/z calcd for C ₂₁ H ₂₄ Br ₂ ([M] ⁺ ): 434.0239, found: 434.0230.

2,3,6,7-tetrabromo-1,1,5,5-tetrabutyl-1,5-dihydro-s-indacene (compound 2o)

Compound 2o was obtained as a white solid (yield 85%) by the same procedure as above, except that compound 1o was used as the starting material.
M. p. :130.5-131℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.17 (s, 2H), 1.88-1.81 (m, 8H), 1.21-1.04 (m, 8H), 0.83-0.71 (m, 16H), 0.48-0.37 (m, 4H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 146.5, 140.6, 136.0, 120.7, 113.2, 60.5, 37.7, 25.1, 22.7, 13.8.
HRMS (APCI+) m/z calcd for C ₂₈ H ₃₈ Br ₄ ([M] ⁺ ): 689.9702, found: 689.9692.

2,3,5,6-tetrabromo-1,1,7,7-tetrabutyl-1,7-dihydro-s-indacene (compound 2p)

Compound 2p was obtained as a white solid (yield 56%) by the same procedure as above, except that compound 1p was used as the starting material.
M. p. :173-174℃.
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.34 (s, 1H), 7.09 (s, 1H), 1.89-1.78 (m, 8H), 1.20-0.99 (m, 8H), 0.86-0.75 (m, 4H), 0.69 (t, J=7.3Hz, 12H), 0.39 (m, 4H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 145.9, 141.4, 135.7, 120.7, 114.8, 112.1, 60.4, 37.5, 25.2, 22.7, 13.7.
HRMS (APCI+) m/z C ₂₈ H ₃₈ Br ₄ ([M] ⁺ ): 689.9702, found: 689.9705.

Synthesis of 5-(2-dibromo-1,1-dibutyl-1H-inden-3-yl)nonan-5-ol (Compound 3)

To a solution (1 mL) of compound 2c (334 mg, 0.86 mmol) in anhydrous THF, n-butyllithium (0.54 mL as a 1.59 M hexane solution) was added at −78°C and stirred at that temperature for 1 hour. Freshly distilled 5-nonanone (122 mg, 0.85 mmol) was added dropwise to this solution and stirred for 30 minutes. The solution was then gradually warmed to room temperature, and aqueous ammonium chloride (5 mL) was added to quench the reaction. The reaction mixture was added to 10 mL of water and extracted with 20 mL of methylene chloride. The organic phase was separated and dried over magnesium sulfate, and the filtrate obtained by filtration was concentrated under reduced pressure. This was purified by silica gel column chromatography (methylene chloride:hexane = 4:1) to obtain compound 3 as a colorless oil (yield 206 mg, 45%). Note that compound 3 is distinct from the compounds represented by the above general formulas (3A) to (3F).
¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) 7.72-7.69 (m, 1H), 7.21-7.15 (m, 3H), 2.55 (s, 1H), 2.28-2.21 (m, 2H), 1.84-1.76 (m, 2H), 1.74-1.6 7 (m, 4H), 1.48-1.38 (m, 2H), 1.34-1.02 (m, 11H), 0.89-0.77 (m, 7H), 0.71 (m, 6H), 0.44-0.33 (m, 2H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 148.8, 143.5, 142.7, 131.6, 126.3, 124.9, 122.2, 121.2, 79.1, 59.7, 41.1, 38.0, 26.0, 25.4, 23.1, 22.9, 14.1, 13.9.
HRMS (APCI+) m/z C ₂₆ H ₄₁ BrO calcd for ([M] ⁺ ): 448.2341, found: 448.2329.

Synthesis of 5,5'-[1,4-phenylenebis(1,1-dibutyl-1H-indene-2,3-diyl)]bis(nonan-5-ol) (Compound 4)

A microwave reactor was charged with compound 3 (206 mg, 0.45 mmol), 1,4-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzene (69.1 mg, 0.21 mmol), Pd ₂ (dba) ₃ (19 mg, 0.021 mmol), triphenylphosphine (16 mg, 0.061 mmol), 1,4-dioxane (0.5 mL), and 2 M aqueous potassium carbonate solution (0.3 mL) and argon gas. The reaction mixture was stirred at 100°C for 2 hours, cooled to room temperature, diluted with chloroform, and passed through a short plug of silica gel. The resulting solution was extracted three times with 10 mL of chloroform. The combined organic phase was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The solvent was removed in vacuo, and the resulting compound 4 was used in the next reaction without further purification. It should be noted that this compound 4 is different from the compound represented by the above general formula (4).

5,5,7,7,12,12,14,14-octabutyl-5,7,12,14-tetrahydrodiindeno[2,1-a:2′,1′-g]-s-indacene (COPV2(Bu))

To a chloroform solution (1 mL) of compound 4 (49 mg, 6.0 × 10 ^-2 mmol), BF ₃ · OEt ₂ (51 mg, 0.36 mmol) was added at room temperature and stirred for 15 minutes. Methanol was then added to the reaction solution to quench the reaction. The resulting solution was concentrated and passed through a short-path silica gel column using hexane as a developing solvent to obtain COPV2(Bu) as a yellow solid (yield: 31 mg, 67%). COPV2(Bu) is a carbon-bridged p-phenylenevinylene derivative of the present invention.
M. p. :205-207℃.
^1H -NMR0 (400MHz, THF-d ₈ ): δ (ppm) 7.36 (s, 2H), 7.32 (d, J=7.7Hz, 4H), 7.21-7.17 (m, 2H), 7.13-7.09 (m, 2H), 2. 25-2.03 (m, 16H), 1.16-1.01 (m, 16H), 0.98-0.80 (m, 8H), 0.77-0.63 (m, 32H).
¹³ C{ ¹ H}-NMR (100 MHz, CDCl ₃ ): δ (ppm) 156.1, 155.7, 154.8, 140.9, 137.6, 126.3, 123.8, 121.8, 118.6, 113.1, 53.8, 53.5, 38.3, 26.9, 26.7, 23.1, 13.8.
HRMS (APCI+) m/z C ₅₈ H ₈₂ ([M] ⁺ ): 778.6417, found: 778.6418.

In COPV2(Bu), a carbon-bridged p-phenylene vinylene derivative of the present invention, all of the bridging carbons are substituted with two butyl groups. As shown in Table 1 of the present specification, this compound has a larger molar absorption coefficient and a larger radiative decay constant in fluorescence emission than COPV2(Ar), in which the bridging carbons are substituted with aryl groups (p-octylphenyl groups). Furthermore, a larger radiative decay constant in fluorescence emission means that the time from excitation to fluorescence decay is shorter, enabling the emission of stronger fluorescence. For these reasons, the carbon-bridged p-phenylene vinylene derivative of the present invention can be said to have superior properties as a fluorescent dye compared to previously known carbon-bridged p-phenylene vinylene derivatives.

Claims (10)

A method for producing a fused polycyclic compound having fused five-membered rings, characterized by reacting a compound having a partial structure represented by the following general formula (1) with an acid to convert it into a compound having a partial structure represented by the following general formula (2):
(The double bond marked with * in the above general formula (1) may be cis- or trans-configured; in general formula (1), R ¹ and R ² are each independently a hydrogen atom, -CQ ₃ , or an aryl group which may have a substituent; or R ¹ and R ² combine to form a ring structure; each Q is each independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino group or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch ; each X is each independently a halogen atom; and the ring structure marked with the symbol Ar is an aromatic ring which may have a substituent. In the above general formula (2), R ¹ and R ² are each independently a hydrogen atom, -CQ ₃ , or an aryl group which may have a substituent; or R ^{R 1} and R ² combine to form a ring structure, each Q is independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch , each X is independently a halogen atom, and the ring structure designated by the symbol Ar is an aromatic ring which may have a substituent. The manufacturing method according to claim 1, wherein the acid is a Lewis acid. The manufacturing method according to claim 2, wherein the Lewis acid is boron trifluoride or a compound formed by binding a Lewis base to boron trifluoride to form a complex. An indacene derivative represented by any one of the following general formulas (3A) to (3F):
(In the above general formulas (3A) to (3F), each R is independently a hydrogen atom, -CQ ₃ , or an aryl group which may have a substituent, or two Rs bonded to the same carbon atom combine to form a ring structure; each Q is independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch ; and each X is independently a halogen atom.) A carbon-bridged p-phenylene vinylene derivative represented by the following general formula (4):
(In the above general formula (4), each R is _-CQ3 , and each Q is independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino group or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch .) The carbon-bridged p-phenylene vinylene derivative according to claim 5, wherein each R in general formula (4) is an n-butyl group. A step i of reacting a compound represented by the following general formula (11) with a first acid to obtain a compound represented by the following general formula (12);
A step ii of reacting a compound represented by the following general formula (12) with an alkyl lithium compound, and then reacting the compound represented by the following general formula (13) to obtain a compound represented by the following general formula (14);
Step iii: subjecting a compound represented by the following general formula (14) to a coupling reaction with a 1,4-phenylenediboronic acid compound to obtain a compound represented by the following general formula (15);
and step iv of reacting a compound represented by the following general formula (15) with a second acid to obtain a compound represented by the following general formula (16):
(In the above chemical reaction formula, each X is independently a halogen atom; each ^R1 and ^R2 is independently a hydrogen atom, _-CQ3 , or an aryl group which may have a substituent; or ^R1 and ^R2 combine to form a ring structure; each ^R3 and ^R4 is independently a hydrogen atom, _-CQ3 , or an aryl group which may have a substituent; or ^R3 and ^R4 combine to form a ring structure; and each Q is independently a hydrogen atom , an alkyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkoxy group having 1 to 12 carbon atoms which may have a heteroatom or a branch, an alkylsulfanyl group having 1 to 12 carbon atoms which may have a heteroatom or a branch, or an alkylamino group or alkylaryl group having 1 to 12 carbon atoms which may have a heteroatom or a branch .) The manufacturing method according to claim 7, wherein the first acid and the second acid are both Lewis acids. The manufacturing method according to claim 8, wherein the Lewis acid is boron trifluoride or a compound formed by binding a Lewis base to boron trifluoride to form a complex. 8. The method according to claim 7, wherein all of R ¹ , R ² , R ³ and R ⁴ are n-butyl groups.