JPS5917088B2 - Method for producing 1,1,1-trichloro-4-methylpentene - Google Patents

Description

[Detailed description of the invention] The present invention is based on the general formula (1) Represents one CH2-C-CH2 group.

) is related to a method for producing 1,1,1-trichloro-4-methylbenzene.

More specifically, the present invention is based on the general formula () (wherein R1 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an acyl group).

) is dehydrated and dealcoholized in the presence of an acidic catalyst selected from the group consisting of sulfuric acid, phosphoric acid, p-toluenesulfonic acid, alkylsulfonic acid, phosphorus pentoxide, vanadium pentoxide, and tungsten trioxide. Or the general formula (1) characterized by subjecting it to decarboxylation reaction
) and general formula () [wherein R1 has the same meaning as in general formula ()].

] To dimethylvinyl carbinol or its derivatives, chloroform is added under radical reaction conditions to obtain a compound represented by the general formula (), which is then treated with sulfuric acid, phosphoric acid,
It is characterized by subjecting it to a dehydration reaction, dealcoholization reaction or decarboxylation reaction in the presence of an acidic catalyst selected from the group consisting of p-toluenesulfonic acid, alkylsulfonic acid, phosphorus pentoxide, vanadium pentoxide and tungsten trioxide. The present invention relates to a method for producing 1,1,1-trichloro-4-methylbenzene represented by the general formula (1).

In general formula () and general formula (), R1 is preferably a hydrogen atom, a methyl group, an ethyl group, a propyl group, a butyl group, an acetyl group, or a butyryl group.

1・represented by general formula (1) obtained by the method of the present invention
1,1-trichloro-4-methylbenzene is a compound of 2,2-dimethyl-3-(2,2
-dichloropinyl) is an important synthetic intermediate of cyclopropane carboxylic acid ester.

Synthetic pyrethroids have the disadvantage of rapid photodegradation of natural pyrethroid insecticides, but are superior in terms of sustainability and insecticidal efficacy [M. EllOtt et al., Natu
rel244, 456 (1973)].

Recently, as a method for synthesizing cyclopropanecarboxylic acid ester for synthetic pyrethroid, a method was reported in JP-A-49-47531, in which chrysanthemum acid is ozonolyzed to obtain the corresponding aldehyde, which is then subjected to Wittig reaction.

However, since this method uses expensive chrysanthemum acid as a starting material and requires complicated operations such as an ozone oxidation reaction and a Wittig reaction, it is considered difficult to adopt it as an industrial method. Also J. Farkas et al. COllect. Czech. Chem. Commun
．． , 24, 2230 (1959), reported the diazoacetate method.

That is, after acetylating 1,1,1-trichloro-4-methyl-3-benzene-2-ol, it was reduced with zinc acetic acid to obtain 1,1-dichloro-4,4-dimethylbutadiene, which was further converted into known Cyclopropanecarboxylic acid ester is produced by reacting with diazoacetic acid ester using the method described in the following. However, this method also requires a long reaction step to synthesize the raw material 1,1-dichloro-4,4-dimethylbutadiene, requires a complicated operation of zinc acetic acid reduction, and has a low yield of addition reaction of diazoacetate. %
It cannot be said to be an industrial method because of its shortcomings, such as low yield. As a result of intensive and detailed investigation into a new and effective synthetic route for the above-mentioned synthetic pyrethroids, the present inventors found that the above-mentioned F.
1,1-dichlor-4,4 used by Arkas et al.
-General formula (1) that can be easily derived into dimethylbutadiene
We have discovered a new method for producing 1,1,1-trichloro-4-methylbenzene represented by the formula, and have completed the present invention.

A compound represented by the general formula () can be produced by reacting dimethylvinyl carbinol represented by the general formula () or a derivative thereof with chloroform under radical reaction conditions.

Radical reaction conditions can be achieved by the presence of a radical reaction initiator or by irradiation with light. As a radical reaction initiator, benzoyl peroxide (BPO),
Azobisisobutyronitrile (AIBN), acetyl peroxide, lauryl peroxide, di-tert-butyl peroxide, tert-butyl peracetate, peracetic acid, tert-perbenzoate
Butyl, tert-butyl perphthalate, tert-butyl hydroperoxide, cumene hydroperoxide, etc. can be used. The radical reaction initiator may be used in a contact amount. The reaction temperature is preferably room temperature to 100°C when light is used as the radical reaction initiation method, and 70 to 180°C when a radical reaction initiator is used. Conventionally, in the radical addition reaction of primary allyl alcohol, its ether, or ester with haloform, for example, Kharasch et al. Am. Chem. S
Oc. , reported in Saradan, 1105 (1947), Lew
is et al. Am. Chem. SOc. , 76, 457
(1954), a large amount of teloma is generated, and Tarrant et al. Org. Chem. ,
one-on-one as stated in Theft 5, 4646 (1961).
The yield of adduct is as low as 20-30%.

Furthermore, it is known that tertiary allyl alcohol such as dimethylvinyl carbinol easily undergoes a dehydration reaction under heating. However, when dimethylvinyl carbinol represented by the general formula () and chloroform are reacted under radical reaction conditions as described above, no dehydration reaction or generation of telomere occurs. For example, chloroform 4
Dimethylvinyl carbinol 4007 was dissolved in 0007, and tert-butyl perbenzoate 307 was added thereto.
After reacting at 0°C for 30 hours, excess chloroform and unreacted dimethylvinylcarbinol were recovered under reduced pressure, and the residue was distilled to give 1.1.1-trichloro-4 with a yield of 82%. Methyl-4-pentanol is obtained. A compound represented by the general formula () is combined with a strong to weakly acidic acidic catalyst selected from the group consisting of sulfuric acid, phosphoric acid, p-toluenesulfonic acid, alkylsulfonic acid, phosphorus pentoxide, vanadium pentoxide, and tungsten trioxide. By subjecting it to a dehydration reaction, dealcoholization reaction or decarboxylation reaction in the presence of the compound, 1.1.1-trichloro4-methylbenzene represented by the general formula (1) can be obtained.

This reaction is carried out at room temperature to 200°C, preferably from 80 to 170°C.
It is carried out over a temperature range of The acidic catalyst can be used in an amount of 0.01 to 30% by weight based on the compound (), preferably in a range of 0.1 to 10% by weight based on the compound (). In the dehydration reaction, dealcoholization reaction, or decarboxylation reaction of the compound represented by the general formula (), the conversion rate of the compound () is usually 95% or more, and 1.1.
A selectivity of 98% or more to 1-trichloro-4-methylbenzene (1) can be achieved.

The ratio of 1,1,1-trichloro-4-methyl-3-benzene to 1,1-trichloro-4-methyl-4-benzene in 1,1,1-trichloro-4-methylbenzene (1) is usually ( 60-90) vs. (40-10);
1,1,1-trichloro-4-methyl- by precision distillation
3-Benzene can be extracted with high purity.

At this time, 1,1,1-trichloro-4methyl-4-benzene obtained as a pre-distillate is returned to the reaction system in the presence of the acidic catalyst.
It can be isomerized to 4-methyl-3-benzene.
1,1,1-trichlor-4 obtained by the method of the present invention
-By treating methyl-3-benzene with a base, 1
- Can be 1-dichloro-4,4-dimethylbutadiene.

Bases used include alkali metal or alkaline earth metal hydroxides such as sodium hydroxide, potassium hydroxide, and calcium hydroxide; sodium methoxide, sodium ethoxide, potassium methoxide, and sodium T.
Metal alkoxides such as ert-butoxide, potassium tert-butoxide, and sodium tert-amyl oxide; alkali metal hydrides such as sodium hydride and potassium hydride; alkali metal amides such as sodium amide; 1.5 diazapine glow [3.4.0] nonene-5 (abbreviated as DBN), 1,5-diazabicyclo [
5.4.O] Organic amines such as undecene-5 (abbreviated as 0BU) and 2-dimethylamino-1-pyrroline; Examples include organic lithium compounds such as n-butyllithium, s-butyllithium, and diisopropylaminolithium. However, from the viewpoint of economy and reaction efficiency, alkali metal alkoxides or alkali metal hydrides,
Preference is given to using alkali metal hydroxides. The amount of the base used is 1 molar equivalent or more, preferably 1 to 2 molar equivalents, based on the raw material. The reaction is preferably carried out in a solvent, and examples of the solvent include an aqueous solvent, an alcoholic solvent such as methanol and ethanol, N-N-dimethylformamide (DMF),
Examples include aprotic polar solvents such as dimethyl sulfoxide (DMSO) and hydrocarbons such as benzene and toluene.

When using organic amines, they may be used in excess to also serve as a solvent. Reaction temperature is room temperature ~1
The temperature range is 50°C, preferably 50-130°C.
The 1,1-dichloro-4,4-dimethylbutadiene thus obtained can be used as an insecticide or an intermediate for its synthesis by reacting with diazoacetate, as reported by Farlcas et al. It can be 2,2-dimethyl-3-(2,2-dichlorovinyl)cyclopropanecarboxylic acid ester.

Hereinafter, the present invention will be explained in more detail with reference to Examples and Reference Examples.

Example 1 Dimethylvinyl carbinol 4001 was dissolved in chloroform 40007, tert-butyl perbenzoate 307 was added thereto, and the reaction was carried out at 110°C for 30 hours. Excess chloroform and unreacted were removed from the reaction solution. Dimethylvinyl carbinol was recovered under reduced pressure to obtain a reddish-yellow viscous liquid 8357 as a residue.

This product has a purity of 9 as a result of gas chromatography analysis.
0.4% 1.1.1-trichloro-4-methyl-4-
It was pentanol and contained 8.7% of 1,1,3-trichloro-4-methyl-4-pentanol as an impurity. By vacuum distilling the above residue, Bp6O~6
High purity 1.1.1-trichloro-4-methyl-4-pentanol was obtained at 732 V as a fraction at 1.5° C. (0.3 m7 ILHg). When left alone, this substance turned into white crystals. The compound was confirmed by the following method. Infrared absorption spectrum Mass spectrum Nuclear magnetic resonance spectrum δ1θA 14 (-11 -1 - - - -1 -1゛ -
-1゛ -14 then 1,1,1-trichlor-
Add 4-methyl-4-pentanol 732y1<p-toluenesulfonic acid 7.3y and heat at 155-160°C.
．． The mixture was heated for 5 hours, and the reaction was carried out while expelling by-product water from the system.

The reaction solution was directly distilled off under reduced pressure of 200 mmHg.
The distillate was dried with borax and then subjected to precision distillation, resulting in 627 pieces of 1,1,1-trichloro-4-methyl-4-benzene as a fraction with Bp73-7'C (20mlHg). , 1,1,1-trichloro-4-methyl-3- as a fraction with Bp74-77℃ (20m7!LHg)
5367 benzene was obtained. The structure of the product was confirmed by the following method. Mass spectrum nuclear magnetic resonance spectrum δ! )÷SOl4 Infrared absorption spectrum ~ Mass spectrum Nuclear magnetic resonance spectrum BΣ014 ~ Examples 2 to 6 Compound ( ) was heated in the presence of an acidic catalyst to perform a de-RlOH reaction in the same manner as in Example 1, and the resulting reaction mixture ( 1) is separated by distillation to obtain 1,1,1-trichol-4-methyl-3.
-benzene and 1,1,1-trichloro-4-methyl-4-benzene were taken out.

The results are shown in Table 1. The compound () used was synthesized by reacting the corresponding /2♂2 in 10 times the weight of chloroform in the presence of a radical reaction initiator at a temperature in the range of 100 to 130°C.

Example 7 0.8y of benzoyl peroxide was added to a solution of 17.2y of dimethyl vinyl carbinol in 150ml of chloroform.
was added thereto, and the reaction was carried out in an autoclave at 135° C. for 18 hours under a nitrogen atmosphere.

After the reaction, unreacted dimethylvinyl carbinol and chloroform were collected by distillation under reduced pressure, and a dark red viscous liquid 30.17 was obtained as a residue. By vacuum distilling this product, 28.27 of 1,1,1-trichloro-4-methyl 4-pentanol was obtained as a fraction of Bp6O to 61.5°C (0.3 mmHg). (Yield 69%). This is a gas chromatography analysis (SlllcOneD).
C-550, 160°C), the purity was found to be 95.4%. The impurity was estimated to be the isomer 1,1,3-trichloro-4-methyl-4-pentanol from the mass spectrum. Then 50 m of 1,1,1-trichloro-4-methyl 4-pentanol in benzene
1 solution was added with 0.19 g of p-toluenesulfonic acid and heated, and refluxed for 2 hours while expelling by-product water from the system by azeotropy.

After the reaction, the solvent was distilled off under reduced pressure, and the residue was vacuum distilled to give a fraction with a Bp of 74 to 77°C (19 mmHg) of 1.1
・1-trichloro-4-methyl-4-benzene and 1
- 8.5y of a mixture of 1,1-trichloro-4-methyl-3-benzene was obtained (yield 9.2%). As a result of gas chromatography analysis of this product, the ratio of 1,1,1-trichloro-4-methyl-4-benzene to 1,1,1-trichloro-4-methyl-3-benzene was approximately 33:67. I found out.

Each compound was separated by precision distillation of the above mixture. Examples 8 to 13 1.1.1-trichlor-4 obtained by the method of Example 7
-Methyl-4-pentanol 5.07 ml was subjected to a dehydration reaction under various conditions.

The results are shown in Table 2. In addition, Examples 8, 12 and 13
In this method, by-produced water was expelled from the reaction system by azeotropy. Examples 14-20 After reacting various dimethylvinyl carbinol derivatives with chloroform under various radical reaction conditions in the same manner as in Example 7, excess chloroform and unreacted dimethyl vinyl carbinol derivatives were collected, and the residue was purified. The product was directly subjected to the next R1OH removal reaction without any further treatment.

The results are summarized in Table 3. Note that all radical addition reactions were performed under an inert gas atmosphere.

Reference Example 1 1,1,1-Trichloro-4-methyl-3-benzene 1867 obtained in Example 1 was placed in 13 500 m flasks, and 1,5-diazapine glow [5,4
・0] Undecene-5 (DBU) 183y was dropped.

After the dropwise addition, the reaction was carried out at room temperature for 1 hour and further at 70°C for 2 hours. The reaction solution was poured into 500 ml of water, extracted with ether, the extract was washed with water, dried, and the solvent was distilled off under reduced pressure. By vacuum distilling the residue, Bp64~
1.1-dichloro-4.4-dimethylbutadiene 137y was obtained as a fraction at 65° C. (20 mmHg). The structure of this product was confirmed by the following method. Infrared absorption spectrum Mass spectrum Nuclear magnetic resonance spectrum δ1nCC14 PPm Reference example 2 1.1.1-trichlor-4 obtained by the method of Example 1
-300ml of 130.2y of methyl-3-benzene
A solution of sodium 23f7 in 150 ml of methanol was added dropwise to the flask at 65°C.

After the dropwise addition, the reaction was continued at the same temperature for an additional 3 hours, and after cooling, the precipitated crystals were filtered under reduced pressure. The filtrate was concentrated to 150 ml under reduced pressure, poured into water, and then extracted with ether. The extract was washed with saturated brine, dried, and the solvent was distilled off under reduced pressure. The residue was vacuum distilled to obtain 98.77 g of 1,1-dichloro-4,4-dimethylbutadiene. Reference example 3 1.1.1-trichlor-4 obtained by the method of Example 1
30 y of powdered potassium hydroxide was added to 657 ml of -methyl-3-benzene, and the reaction was carried out at 120 to 125° C. for 5 hours with stirring.

Claims (1)

[Claims] 1. General formula (II) ▲Contains mathematical formulas, chemical formulas, tables, etc.▼……(II) (In the formula, R^1 is a hydrogen atom, an alkyl group, a cycloalkyl group,
Represents an aryl group, an aralkyl group or an acyl group. ) is dehydrated and dealcoholized in the presence of an acidic catalyst selected from the group consisting of sulfuric acid, phosphoric acid, p-toluenesulfonic acid, alkylsulfonic acid, phosphorus pentoxide, vanadium pentoxide, and tungsten trioxide. Or the general formula (
I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼……(I)
(In the formula, Z represents ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼.) A method for producing 1,1,1-trichloro-4-methylpentene. 2 General formula (II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼…………(III) (
In the formula, R^1 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an acyl group. ) by adding chloroform to dimethylvinyl carbinol or its derivatives under radical reaction conditions to form the general formula (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼......(
II) [In the formula, R^1 has the same meaning as in general formula (III). ] was obtained, and this was mixed with sulfuric acid, phosphoric acid, p-toluenesulfonic acid, alkylsulfonic acid, phosphorus pentoxide,
The general formula (I) is characterized by being subjected to a dehydration reaction, dealcoholization reaction or decarboxylation reaction in the presence of an acidic catalyst selected from the group consisting of vanadium pentoxide and tungsten trioxide. There is▼……
...(I) (In the formula, Z represents ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼.) 1,1,1-trichloro-4-methylpentene manufacturing method.