JP4904504B2 - Process for producing optically active helical polymer and polymerization initiator for optically active helical polymer - Google Patents

Description

  The present invention relates to a method for producing an optically active helical polymer and an optically active helical polymer polymerization initiator.

  Synthetic polymers around us generally have a random structure. On the other hand, there are many biopolymers typified by DNA and proteins that are helical in one direction. These biopolymers are responsible for the “molecular recognition ability” that distinguishes the right-handed and left-handed bodies of chiral substances, “catalysis” that separates the right-handed and left-handed bodies, self-replication, self-replication, and information transmission. It has functions unique to the helical structure such as “information function”, and these functions are considered to play an important role in the expression of advanced functions essential for life support.

  By the way, not only biopolymers but also artificially synthesizing polymers having specific functions have been studied. Japanese Patent Application Laid-Open No. 2004-27207 discloses that a template polymer compound is created by copolymerizing an acrylic acid derivative and a crosslinkable monomer to give molecular recognition, and can be used as a stationary phase for chromatography.

  Further, in Japanese Patent Application Laid-Open No. 2004-263071, a liquid crystal compound is used as a solvent, and the anisotropic properties of the liquid crystal compound are used to twist in one direction while maintaining the conductivity that is a specific function of polyacetylene. A process for producing a polyacetylene having a helical or spiral structure is described. Such polyacetylene is a powerful model for molecular solenoids made of molecular copper wire, and is expected to make a great leap forward toward the realization of electrical and magnetic functional elements. However, when polymerizing a helical polymer using a liquid crystal compound as an asymmetric anisotropy reaction field, liquid crystal properties will not be exhibited if the number of substances that disturb the aligned liquid crystal increases. Polymerization must be carried out while maintaining the ratio of the amount of polyacetylene to the amount at a small value and maintaining the orientation of the liquid crystal. In addition, liquid crystal molecules are extremely expensive compared to commonly used organic solvents, and there is a problem that application to mass production is impossible.

  By the way, poly (quinoxaline-2,3-diyl) is a characteristic polymer that does not show denaturation or decrease in optical purity even in a solution at 100 ° C., and is a material typified by optical isomer separation materials and optical materials. Applications in the scientific field are expected. Conventionally, this polymer has been synthesized by an asymmetric polymerization reaction of a 1,2-diisocyanobenzene derivative using an optically active organopalladium complex as an initiator (Y. Ito, et al. J. Am Chem. Soc., 1998, 120, 11880. and M. Suginome, et al. Org. Lett., 2002, 4, 351.). The polymer produced by this reaction has a helical structure, and when an optically active organopalladium complex is used as the asymmetric polymerization initiator, the helical asymmetry can be almost completely controlled. However, since palladium is expensive, it is not practical and has a problem that the polymerization reaction rate is not so fast.

  The present invention provides a method for producing an optically active helical polymer that is inexpensive and has a high polymerization rate at room temperature by performing asymmetric polymerization using an optically active organonickel complex as an asymmetric polymerization catalyst. A polymerization initiator is provided.

  That is, the present invention includes (A) a step of reacting an aromatic compound or aromatic heterocyclic compound with (B) a nickel compound in the presence of (C) a ligand, and (D) adjacent to the reactant. A method for producing an optically active helical polymer comprising a step of mixing a diisonitrile compound having an isonitrile group with two unsaturated carbons and polymerizing the diisonitrile compound, wherein the aromatic compound or the aromatic heterocyclic compound (A ) And at least one of the ligands (C) is optically active, and relates to a method for producing an optically active helical polymer.

  The diisonitrile compound (D) is preferably represented by the following formula (I).

（式中、Ｒ¹〜Ｒ⁴は同じかまたは異なってもよく、それぞれ水素、置換されても良い直鎖または分岐アルキル基、置換されても良いアリール基、置換されても良い芳香族複素環基、置換されても良い脂肪複素環基、ハロゲン原子、シアノ基、ニトロ基、カルボキシル基、置換されても良いアミノ基、置換されても良いアルコキシル基、置換されても良いカルバモイル基から選択される基のうちのいずれかである。また、Ｒ¹とＲ³、Ｒ³とＲ⁴あるいはＲ⁴とＲ²がそれぞれ環を成す構造でも良い。）

(Wherein R ^{1 to} R ⁴ may be the same or different, and each represents hydrogen, an optionally substituted linear or branched alkyl group, an optionally substituted aryl group, and an optionally substituted aromatic heterocyclic ring. Group, an optionally substituted aliphatic heterocyclic group, a halogen atom, a cyano group, a nitro group, a carboxyl group, an optionally substituted amino group, an optionally substituted alkoxyl group, and an optionally substituted carbamoyl group. And R ¹ and R ³ , R ³ and R ^4, or R ⁴ and R ² may each form a ring.)

In the diisonitrile compound (D) represented by the formula (I), R ¹ and R ² and / or R ³ and R ⁴ are preferably the same substituent.

  The diisonitrile compound (D) is preferably represented by the following formula (II).

（式中、Ｙは酸素または硫黄、Ｒは炭素数１〜１２のアルキル基を示し、ｍおよびｎはそれぞれ１≦ｍ≦１２、０≦ｎ≦１１、かつ１≦ｍ＋ｎ≦１２の関係を満たす整数である。）

(Wherein Y represents oxygen or sulfur, R represents an alkyl group having 1 to 12 carbon atoms, and m and n satisfy the relations 1 ≦ m ≦ 12, 0 ≦ n ≦ 11, and 1 ≦ m + n ≦ 12, respectively. (It is an integer.)

（式中、Ｍｅはメチル基を示す。）

(In the formula, Me represents a methyl group.)

  The ligand of the nickel complex (B) is preferably 1,5-cyclooctadioene.

  The aromatic compound or the aromatic heterocyclic compound (A) is preferably represented by the following formula (IV) or (V).

（式中、Ｘはハロゲン基、Ｒ^*は光学活性な置換基を示す。）

(In the formula, X represents a halogen group, and R ^* represents an optically active substituent.)

  The aromatic compound or the aromatic heterocyclic compound (A) is preferably represented by the following formula (VI) or (VII).

（式中、Ｘはハロゲン基、Ｒ’はアセチル基、ホルミル基またはメトキシカルボニル基のうちのいずれかであり、Ｐｈはフェニル基、ｔｏｌはトリル基を示す。）

(In the formula, X represents a halogen group, R ′ represents one of an acetyl group, a formyl group, and a methoxycarbonyl group, Ph represents a phenyl group, and tol represents a tolyl group.)

  The ligand (C) is preferably a trialkylphosphine.

  The present invention also relates to an optically active helical polymer polymerization initiator in which an optically active aryl group is bonded to nickel.

  It is preferable that a halogen group or a pseudohalogen group is further bonded to nickel.

  The optically active aryl group is preferably represented by the following formula (VIII) or (IX).

（式中、Ｒ^*は光学活性な置換基を示す。）

(In the formula, R ^* represents an optically active substituent.)

  The optically active aryl group is preferably represented by the following formula (X) or (XI).

（式中、Ｒ’はアセチル基、ホルミル基またはメトキシカルボニル基のうちのいずれかであり、Ｐｈはフェニル基、ｔｏｌはトリル基を示す。）

(In the formula, R ′ is any one of an acetyl group, a formyl group, and a methoxycarbonyl group, Ph is a phenyl group, and tol is a tolyl group.)

  The present invention includes (A) a process of reacting an aromatic compound or aromatic heterocyclic compound with (B) a nickel compound in the presence of (C) a ligand, and (D) two adjacent groups. A process for producing an optically active helical polymer comprising a step of mixing a diisonitrile compound each having an isonitrile group with unsaturated carbon to polymerize the diisonitrile compound, the aromatic compound or aromatic heterocyclic compound (A) And at least one of the ligands (C) is optically active, and relates to a method for producing an optically active helical polymer.

  In the aromatic compound or aromatic heterocyclic compound (A), the mother nucleus of the aromatic compound or aromatic heterocyclic compound is not particularly limited, but hydrocarbons such as benzene, naphthalene, phenanthrene, pyridine, pyrrole, indole , Heterocyclic rings such as thiophene, furan, pyrazole, pyrimidine, quinoline and quinoxaline. Of these, benzene and naphthalene are preferably used from the viewpoint of easy availability of raw materials and synthesis, and quinoxaline is also preferable from the structural similarity to the polymerization intermediate. Furthermore, 1,2-diisocyano-3,6-di-para-tolylbenzene is preferable as an optional component in that the polymerization initiator can be isolated as a complex and handling properties can be improved.

The substituent of such an aromatic compound or aromatic heterocyclic compound (A) is not particularly limited, but halogens such as fluorine, chlorine, bromine and iodine, alkylsulfonyloxy groups (RSO ₃ —, for example, TsO (TsO Represents tosylate), TfO (TfO represents triflate), etc.), acyloxy group (RCO ₂ — such as AcO (Ac represents acetyl group), BzO (Bz represents benzoyl), etc. ), Or pseudohalogens such as O = P (OR) ₂ O, and metal halides such as magnesium halide. Of these, chlorine, bromine and iodine are preferably used from the viewpoint of easy availability and easy preparation of nickel compounds.

  Examples of such a compound (A) include, but are not limited to, binaphthyl derivatives, biphenyl derivatives, ferrocene derivatives having asymmetric carbon, axial asymmetry or plane asymmetry. Specific examples include chiral aromatic compounds represented by the following formula, and among them, compounds represented by the following formula (IV) or (V), particularly the following formula (VI) or (VII) are preferable.

  Furthermore, examples of the binaphthyl derivative, imidazole derivative, and oxazole derivative having asymmetric carbon, axial asymmetry or plane asymmetry include compounds represented by the following formulae.

（式中、Ｘはハロゲン基、Ｒ^*は光学活性な置換基、Ｒ’はアセチル基、ホルミル基またはメトキシカルボニル基のうちのいずれかであり、Ｐｈはフェニル基、ｔｏｌはトリル基、Ａｒはアリール基、ＲおよびＲ¹〜Ｒ⁷はそれぞれ水素、置換されても良い直鎖または分岐アルキル基、置換されても良いアリール基、置換されても良い芳香族複素環基、置換されても良い脂肪複素環基、ハロゲン原子、シアノ基、ニトロ基、カルボキシル基、置換されても良いアミノ基、置換されても良いアルコキシル基、置換されても良いカルバモイル基から選択される基のうちのいずれかであり、Ｒ¹〜Ｒ⁴の少なくとも１種が他の置換基と異なる。また、Ｒ⁵〜Ｒ⁷はそれぞれ異なる。）ここで、置換されても良いとは、前記置換基にさらに、メチル基、エチル基、プロピル基、ブチル基、イソプロピル基、イソブチル基、sec-ブチル基などのアルキル基、フェニル基、トリル基、キシリル基、メシチル基等のアリール基、ベンジル基や２−フェニルエチル基等のアラルキル基、ピリジル基、ピロリル基、フリル基等の芳香族複素環基、ハロゲン原子、シアノ基、ニトロ基、カルボキシル基などの置換基で置換されてもよいことを意味する。

(Wherein X is a halogen group, R ^* is an optically active substituent, R ′ is any one of an acetyl group, a formyl group or a methoxycarbonyl group, Ph is a phenyl group, tol is a tolyl group, and Ar is The aryl group, R, and R ^{1 to} R ⁷ are each hydrogen, an optionally substituted linear or branched alkyl group, an optionally substituted aryl group, an optionally substituted aromatic heterocyclic group, and optionally substituted. Any one of a group selected from an aliphatic heterocyclic group, a halogen atom, a cyano group, a nitro group, a carboxyl group, an optionally substituted amino group, an optionally substituted alkoxyl group, and an optionally substituted carbamoyl group And at least one of R ^{1 to} R ⁴ is different from the other substituents, and R ^{5 to} R ⁷ are different from each other. Group Alkyl group such as thiol group, propyl group, butyl group, isopropyl group, isobutyl group and sec-butyl group, aryl group such as phenyl group, tolyl group, xylyl group and mesityl group, benzyl group and 2-phenylethyl group It means that it may be substituted with a substituent such as an aromatic heterocyclic group such as aralkyl group, pyridyl group, pyrrolyl group and furyl group, halogen atom, cyano group, nitro group and carboxyl group.

The nickel compound (B) is not particularly limited, but a nickel zero-valent complex such as Ni (cod) ₂ (cod means 1,5-cyclooctadiene), NiCl ₂ , NiBr ₂ , Ni (acac) ₂ And nickel divalent compounds such as (acac means acetylacetone). Of these, Ni (cod) ₂ is preferably used.

  The ligand (C) is not particularly limited as long as it can coordinate to nickel, and examples thereof include trialkylphosphine, dialkylarylphosphine, alkyldiarylphosphine, triarylphosphine, pyridine derivatives, bipyridine derivatives, and phenanthroline derivatives. It is done. Of these, trimethylphosphine is preferably used. Examples of the optically active ligand (C) include optically active tertiary phosphine, optically active diphosphine, optically active carbene, optically active tertiary amine, optically active sulfide, and optically active 1 having active hydrogen capable of deprotonation. Examples include secondary or secondary amines, optically active carboxylic acids, optically active alcohols, optically active thiols and their deprotonated anion bodies.

  In the present invention, it is sufficient that at least one of the aromatic compound or aromatic heterocyclic compound (A) and the ligand (C) is optically active.

  In the production method of the present invention, a diisonitrile compound (D) having an isonitrile group in two adjacent unsaturated carbons is used as the monomer. Although it will not specifically limit if it is a compound which has two or more isonitrile groups as a diisonitrile compound (D), It is preferable that two isonitrile groups are substituted by the cis position of the aromatic ring. Specifically, a 1,2-diisocyanobenzene derivative which is a compound represented by the following formula (I) is preferable.

（式中、Ｒ¹〜Ｒ⁴は同じかまたは異なってもよく、それぞれ水素、置換されても良い直鎖または分岐アルキル基、置換されても良いアリール基、置換されても良い芳香族複素環基、置換されても良い脂肪複素環基、ハロゲン原子、シアノ基、ニトロ基、カルボキシル基、置換されても良いアミノ基、置換されても良いアルコキシル基、置換されても良いカルバモイル基から選択される基のうちのいずれかである。また、Ｒ¹とＲ³、Ｒ³とＲ⁴またはＲ⁴とＲ²がそれぞれ環を成す構造でも良い。）

(Wherein R ^{1 to} R ⁴ may be the same or different, and each represents hydrogen, an optionally substituted linear or branched alkyl group, an optionally substituted aryl group, and an optionally substituted aromatic heterocyclic ring. Group, an optionally substituted aliphatic heterocyclic group, a halogen atom, a cyano group, a nitro group, a carboxyl group, an optionally substituted amino group, an optionally substituted alkoxyl group, and an optionally substituted carbamoyl group. And R ¹ and R ³ , R ³ and R ^4, or R ⁴ and R ² may each form a ring.)

In the above formula (I), R ^{1 to} R ⁴ may be the same or different and are each hydrogen, a linear or branched alkyl group that may be substituted, an aryl group that may be substituted, or an aromatic that may be substituted. Group heterocyclic group, optionally substituted aliphatic heterocyclic group, halogen atom, cyano group, nitro group, carboxyl group, optionally substituted amino group, optionally substituted alkoxyl group, optionally substituted carbamoyl group Any of the groups selected from Further, a structure in which R ¹ and R ³ , R ³ and R ^4, or R ⁴ and R ² each form a ring may be employed. Here, it may be substituted means that the substituent is further substituted with an alkyl group such as methyl group, ethyl group, propyl group, butyl group, isopropyl group, isobutyl group, sec-butyl group, phenyl group, tolyl group, Aryl group such as xylyl group, mesityl group, aralkyl group such as benzyl group and 2-phenylethyl group, aromatic heterocyclic group such as pyridyl group, pyrrolyl group, furyl group, halogen atom, cyano group, nitro group, carboxyl group It means that it may be substituted with a substituent such as.

In the diisonitrile compound (D) represented by the formula (I), those in which R ¹ and R ² and / or R ³ and R ⁴ are the same substituents are used for the structural stability and controllability of the resulting helical polymer. In terms of contribution to improvement, the diisonitrile compound represented by the following formula (II), particularly the following formula (III) is particularly preferred.

（式中、Ｙは酸素または硫黄、Ｒは炭素数１〜１２のアルキル基を示し、ｍおよびｎはそれぞれ１≦ｍ≦１２、０≦ｎ≦１１、かつ１≦ｍ＋ｎ≦１２の関係を満たす整数である。）

(Wherein Y represents oxygen or sulfur, R represents an alkyl group having 1 to 12 carbon atoms, and m and n satisfy the relations 1 ≦ m ≦ 12, 0 ≦ n ≦ 11, and 1 ≦ m + n ≦ 12, respectively. (It is an integer.)

  The alkyl group having 1 to 12 carbon atoms in R of the chemical formula (II) is preferably a methyl group or an ethyl group, more preferably both R are the same substituent, and the diisonitrile compound of the above formula (II). It is preferable that R in (D) is represented by the following formula (III) in which both are methyl groups.

（式中、Ｍｅはメチル基を示す。）

(In the formula, Me represents a methyl group.)

  The step of reacting (A) the aromatic compound or aromatic heterocyclic compound with (B) the nickel compound in the presence of the (C) ligand may be performed under basic conditions. In that case, examples of the base used include pyridine, trialkylamine, imidazole, t-butoxypotassium, and t-butoxysodium.

  Examples of the solvent for the asymmetric polymerization of the diisonitrile compound (D) include tetrahydrofuran (THF), 1,4-dioxane, toluene, benzene, xylene, diethyl ether, hexane, isopropyl alcohol, dichloromethane, chloroform and the like. It is done. These may be used alone or as a mixture of two or more. Of these, THF is preferably used.

  After polymerization, a polymerization terminator may be added to the reaction system. Examples of the polymerization terminator include alkyl lithium, aryl lithium, diisobutyl aluminum hydride, metal zinc, metal aluminum, lithium aluminum hydride, sodium borohydride and the like.

  The reaction temperature is preferably -20 to 60 ° C. When the reaction temperature is lower than −20 ° C., the reaction rate is lowered, and a helical polymer having a sufficient molecular weight cannot be obtained, resulting in a problem in the solubility of the produced polymer. Moreover, when it exceeds 60 degreeC, there exists a tendency for molecular weight distribution to become wide and for a spiral direction excess rate to fall.

  In addition, as a manufacturing method of the said optically active helical polymer, after reacting compound (A)-(C), the polymerization initiator which is a reaction product is refine | purified, Diisonitrile compound (D) is used using this initiator. The compound (A) to (C) may be reacted and then the diisonitrile compound (D) may be added to carry out the polymerization reaction, or the compounds (A) to (D) may be combined at once. You may mix and perform a polymerization reaction.

  The optically active helical polymer polymerization initiator of the present invention is formed by bonding an optically active aryl group to nickel. In the method for producing an optically active helical polymer, an aromatic compound or an aromatic heterocyclic compound (A ) And the nickel compound (B) in the presence of the ligand (C).

  For the optically active aryl group bonded to nickel, an aryl moiety other than the halogen group in the above-described aromatic compound or aromatic heterocyclic compound (A) can be applied as it is, and among these, the following formula (VIII) or ( IX), particularly those represented by the following formula (X) or (XI).

（式中、Ｒ^*は光学活性な置換基、Ｒ’はアセチル基、ホルミル基またはメトキシカルボニル基、Ｐｈはフェニル基、ｔｏｌはトリル基を示す。）

(In the formula, R ^* represents an optically active substituent, R ′ represents an acetyl group, a formyl group or a methoxycarbonyl group, Ph represents a phenyl group, and tol represents a tolyl group.)

  The optically active group bonded to nickel is not limited to the optically active aryl group, and may be an optically active group among the above-described ligands (C).

  Further, it is preferable that a halogen group or a pseudohalogen group is further bonded to nickel. Examples of the halogen group or pseudo-halogen group include the above-described halogens or pseudo-halogens.

  Examples of the optically active helical polymer produced by the production method of the present invention include poly (quinoxaline-2,3-diyl). The helical structure of poly (quinoxaline-2,3-diyl) is very stable, but there are three factors that affect its stability. (1) Bulkiness of substituents at positions 5 and 8; (2) Degree of polymerization (stable as the chain length increases); (3) Bulkiness of terminal substituents. The effect of the terminal substituents is surprisingly great. When both ends are methyl groups, even if they are racemized at room temperature, only one terminal is bulky aryl group (such as 1,1′-binaphthyl-2-diyl group) ), A polymer that does not racemize at all even when heated at 100 ° C. is obtained.

  In addition, the more stable the helical structure of the polymer, the more the helix that is once formed will not be unwound. Therefore, it is important to develop a polymerization method that controls the direction of the helix kinetically-an asymmetric polymerization method. The helical polymer is synthesized by aromatizing living polymerization of 1,2-diisocyanobenzene using an organic nickel complex as an initiator.

On the other hand, asymmetric living polymerization proceeds by a continuous insertion reaction of an isocyano group into a CM bond. The optically active aryl group (Ar ^* ) possessed by the initiator moves away from the growth end as the polymerization proceeds. Nevertheless, the helix is completely controlled because the helical structure of the helical polymer is extremely rigid. The helical structure is formed in the initial stage of about a trimer, but at this point the left and right helices can still be unwound, and a thermodynamically stable helix is formed by the steric effect of Ar ^* . As the degree of polymerization increases, unwinding becomes less likely and the formation of the helical structure occurs kinetically along the direction of the helix that has already been formed. There are few examples of asymmetric polymerization including such a mechanism, but it will be an effective strategy for the asymmetric synthesis of stable spirals in the future.

  The optically active helical polymer obtained by the production method of the present invention may be a homopolymer or a copolymer, and the copolymer is preferably a block copolymer. Further, the molecular weight of the optically active helical polymer is arbitrary because it varies depending on the reaction conditions and the intended use.

  The optically active helical polymer obtained by the production method of the present invention has optical isomer separation materials such as chiral columns and chiral separation membranes, optical materials such as nonlinear optical materials, chiral polymer materials, chiral polymer catalysts, and helical polymers. It can be used in fields and products that utilize the mechanical strength retention component of living organisms such as skin, the rigid rod shape, and the physical characteristics of the helical structure derived from rigidity.

  In order to develop a new function, it is possible to create a functional helical polymer due to the molecular structure of the substitution machine by introducing a functional substituent in the side chain moiety. It is possible to elucidate the principle of life function expression through a helical polymer and to construct functional materials having conductivity, light emission, liquid crystal properties, photoresponsiveness, ferroelectricity, and the like. Examples of such a substituent include azobenzene, 1,2-diarylethene, polythiophene, porphyrin and the like.

  Furthermore, a helical structure in the desired direction is constructed from a polymer with three-dimensional regularity, and substituents consisting of arbitrary compounds along the helical axis, organic / inorganic compounds, fullerenes, enzymes, etc. can be freely set. The creation of functional helical polymers arranged in tandem can also be expected.

  In addition, not only a single helical polymer, but also an assembly of helical polymers, if precise sequence control becomes possible, “molecular recognition ability”, “catalysis”, “information function (self-replication and self-replication)” It can be expected to be applied as a new chiral material such as chiral identification materials, sensors, membranes, and liquid crystal materials.

  Not only will it lead to the creation of innovative functional materials that surpass the performance of existing polymers, but it can also be expected to make a significant contribution to advances in the field of chiral technology, which is important for medical and pharmaceutical development.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

Example 1 (Synthesis of optically active nickel initiator (1))

In a glove box, Ni (cod) ₂ (bis (η-1,5-cyclooctadiene) nickel (0)) 100 mg (0.36 mmol) was taken in a reaction vessel and dissolved in 4.5 ml of THF, and 1.0 mol / l. Of trimethylphosphine in THF (0.81 ml) was added at room temperature and stirred for 1 hour. A solution prepared by dissolving 151 mg (0.40 mmol) of (4S, 5S) -1-acetyl-2- (2-chlorophenyl) -4,5-diphenyl-4,5-dihydroimidazole in 2.0 ml of THF was prepared separately. The solution prepared above was added at room temperature and stirred for 1 hour. To this reaction mixture, a solution prepared by dissolving 187 mg (0.61 mmol) of 1,2-diisocyano-3,6-di-para-tolylbenzene, which is an optional component, in 3.0 ml of THF was added and stirred at room temperature for 2 hours. After the reaction, the solvent was removed by a rotary evaporator and the residue was purified by column chromatography (hexane: diethyl ether = 10: 1) to obtain 168 mg (0.19 mmol) of an optically active nickel initiator (1). The yield was 52%.

Example 2 (Asymmetric polymerization of diisocyanobenzene (2) using optically active nickel initiator (1))

  In a glove box, 83 μl (4.2 μmol) of a THF solution (0.05 mol / l) of nickel initiator (1) was taken in a reaction vessel, and 6.2 ml of THF was added. A THF solution (1.0 mol / l) of trimethylphosphine (4.2 μl, 4.2 μmol) was added at room temperature and stirred for 15 minutes. A solution prepared by dissolving 50 mg (0.17 mmol) of diisocyanobenzene (2) in 2.1 ml of THF was added at room temperature and stirred for 4 hours. To this solution, 10 mg (0.26 mmol) of sodium borohydride was added and stirred for 15 minutes, and then 10 ml of water was added outside the glove box. After extraction with chloroform, the organic layer was dried over magnesium sulfate, filtered, and the solvent was distilled off with a rotary evaporator to obtain 53.1 mg (4.2 mmol) of quinoxaline polymer (3). The yield was 100%. When the molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the obtained helical polymer were measured by GPC (polystyrene conversion), Mn was 8095 and Mw / Mn was 1.16. The excess ratio in the helical direction was measured and found to be 91%. Further, sampling was performed at intervals of 5 minutes after the start of the reaction, and the reaction was traced. As a result, the polymerization was completed within 5 minutes at the longest.

Example 3 (Asymmetric polymerization of diisocyanobenzene (4) using optically active nickel initiator (1))

  Polymerization was carried out in the same manner as in Example 2 except that diisocyanobenzene (4) in which the methyl group of diisocyanobenzene (2) was replaced with an ethyl group was used, and quinoxaline polymer (5) 31. 7 mg (2.30 μmol) was obtained. The yield was 92%. When the molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the obtained helical polymer were measured by GPC (polystyrene conversion), Mn was 9629 and Mw / Mn was 1.109. The excess ratio in the helical direction was measured and found to be 33%.

Example 4 (Asymmetric polymerization of diisocyanobenzene (2) including preparation of initiator from optically active organic halide)

In the glove box, 1.14 mg (4.2 μmol) of Ni (cod) ₂ (bis (η-1,5-cyclooctadiene) nickel (0)) was taken in a reaction vessel and dissolved in 2.95 ml of THF. 8.3 μl of trimethylphosphine in THF (1.0 mol / l) was added at room temperature and stirred for 1 hour. 1.54 mg (4.2 μmol) of (4S, 5S) -1-acetyl-2- (2-chlorophenyl) -4,5-diphenyl-4,5-dihydroimidazole was dissolved in 1.31 ml of THF and added at room temperature. Stir for hours. To this reaction solution, 1.97 ml of THF was added at room temperature and stirred for 2.5 hours. After adding 4.2 μl (4.2 μmol) of trimethylphosphine in THF (1.0 mol / l) at room temperature and stirring for 15 minutes, 50 mg (1.66 mmol) of diisocyanobenzene (2) was dissolved in 2.08 ml of THF. The solution was added and stirred for 1 hour. After adding 10 mg (0.26 mmol) of sodium borohydride to this solution and stirring for 15 minutes, 10 ml of water was added outside the glove box. After extraction with chloroform, the organic layer was dried over magnesium sulfate, filtered, and the solvent was distilled off with a rotary evaporator to obtain 46.7 mg (3.7 μmol) of quinoxaline polymer (6). When the molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the obtained helical polymer were measured, Mn was 10579 and Mw / Mn was 1.12. Moreover, it was 83% when the spiral direction excess rate was measured. On the other hand, the reaction time was at most 5 minutes as in Example 2.

Example 5 (Asymmetric polymerization of diisocyanobenzene (2) including preparation of initiator from optically active organic halide)

  Polymerization was carried out in the same manner as in Example 4 except that 1.54 mg (5.00 μmol) of 1,2-diisocyano-3,6-di-para-tolylbenzene was added as an optional component, and a quinoxaline polymer ( 3) 50.2 mg (3.96 μmol) was obtained. When the molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the obtained helical polymer were measured, Mn was 5423 and Mw / Mn was 1.35. Moreover, it was 98% when the spiral direction excess rate was measured.

Example 6 (Asymmetric polymerization of diisocyanobenzene (2) including preparation of initiator from optically active organic halide)

  (4S, 5S) -1-acetyl-2- (2-chlorophenyl) -4,5-diphenyl-4,5-dihydroimidazole was converted to (4S, 5S) -1-formyl-2- (2-chlorophenyl) -4 Polymerization was carried out in the same manner as in Example 5 except that it was replaced with 1,5-diphenyl-4,5-dihydroimidazole to obtain 53.9 mg (4.26 μmol) of quinoxaline polymer (7). When the molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the obtained helical polymer were measured, Mn was 8735 and Mw / Mn was 1.15. Moreover, it was 93% when the spiral direction excess rate was measured.

Example 7 (Asymmetric polymerization of diisocyanobenzene (2) including preparation of initiator from optically active organic halide)

  (4S, 5S) -1-acetyl-2- (2-chlorophenyl) -4,5-diphenyl-4,5-dihydroimidazole is converted to (4S, 5S) -1-methoxycarbonyl-2- (2-chlorophenyl)- Polymerization was carried out in the same manner as in Example 5 except for replacing with 4,5-diphenyl-4,5-dihydroimidazole to obtain 51.1 mg (4.03 μmol) of quinoxaline polymer (8). When the molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the obtained helical polymer were measured, Mn was 8006 and Mw / Mn was 1.29. Moreover, it was 70% when the spiral direction excess rate was measured.

Comparative Example 1 (Asymmetric polymerization of diisocyanobenzene (2) using optically active palladium initiator (9))

  1.7 mg (1.7 μmol) of the palladium initiator (9) was dissolved in 3 ml of THF, 2.4 ml of a trimethylphosphine solution in THF (0.7 mmol / l), and then 20 mg (0 of diisocyanobenzene (2) 0.067 mmol) was added and stirred at room temperature for 18 hours. After adding 10 mg (0.26 mmol) of sodium borohydride to this solution and stirring for 1 hour, 3 ml of water was added and extracted with chloroform. The organic layer was dried over magnesium sulfate, filtered, and the solvent was distilled off with a rotary evaporator to obtain a quinoxaline polymer (3). The yield was 86%.

  When the molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the obtained helical polymer were measured, Mn was about 10663 and Mw / Mn was 1.28. Moreover, it was 98% when the spiral direction excess rate was measured. Further, when the reaction was traced by sampling at an interval of 1 hour after the start of the reaction, the raw material remained in 4 hours and progressed by 95% or more in 12 hours.

  According to the method for producing an optically active helical polymer of the present invention, since an optically active nickel complex is used, the optically active polymer can be synthesized at a much lower cost than conventionally used palladium. Further, since the reaction rate is remarkably increased, it is possible to obtain an extremely excellent effect that the time required for polymerization is remarkably shortened.

Claims (7)

(A) a step of reacting an aromatic compound or aromatic heterocyclic compound with (B) a nickel compound in the presence of (C) a ligand, and (D) two adjacent unsaturated carbons with the reactant. A method for producing an optically active helical polymer, comprising the steps of mixing a diisonitrile compound each having an isonitrile group and polymerizing the diisonitrile compound,
The (A) aromatic compound or aromatic heterocyclic compound is represented by the formula (VI):

Or formula (VII):

(In the formula, X is a halogen group, R ′ is any one of an acetyl group, a formyl group, and a methoxycarbonyl group, Ph is a phenyl group, and tol is a tolyl group)
A method for producing an optically active helical polymer , wherein the ligand (C) is a trialkylphosphine . The (D) diisonitrile compound is represented by the formula (I) :

(Wherein R ^{1 to} R ⁴ may be the same or different, and each represents hydrogen, an optionally substituted linear or branched alkyl group, an optionally substituted aryl group, and an optionally substituted aromatic heterocyclic ring. Group, an optionally substituted aliphatic heterocyclic group, a halogen atom, a cyano group, a nitro group, a carboxyl group, an optionally substituted amino group, an optionally substituted alkoxyl group, and an optionally substituted carbamoyl group. that is any of the groups. in addition, but it may also in a structure in which R ¹ and R ^3, R ³ and R ⁴ or R ⁴ and R ² form a respective ring)
The method for producing an optically active helical polymer according to claim 1, which is represented by: Formula (I) (D) Jiisonitoriru Oite the compounds, R ¹ and R ² and / or R ³ and optically active helical polymer ranging second claim of claim R ⁴ are the same substituent Manufacturing method. (D) The diisonitrile compound has the formula (II) :

(Wherein Y represents oxygen or sulfur, R represents an alkyl group having 1 to 12 carbon atoms, and m and n satisfy the relations 1 ≦ m ≦ 12, 0 ≦ n ≦ 11, and 1 ≦ m + n ≦ 12, respectively. Ru integer der)
The method for producing an optically active helical polymer according to claim 3, which is represented by the following formula. (D) The diisonitrile compound has the formula (III) :

(In the formulas, Me shows the methyl group)
The method for producing an optically active helical polymer according to claim 4, which is represented by the following formula. (B) ligand definitive nickel compound, 1,5-cyclooctadiene geo-ene in which claims the first term, the second term, the third term, the fourth term or optically active helix paragraph 5, wherein A method for producing a polymer. An optically active helical polymer polymerization initiator having an optically active aryl group bonded to nickel , wherein the optically active aryl group has the formula (X):

Or formula (XI):

(In the formula, R ′ is any one of an acetyl group, a formyl group, and a methoxycarbonyl group, Ph is a phenyl group, and tol is a tolyl group)
An optically active helical polymer polymerization initiator represented by the formula: