JPH04124150A - Production of (2,2)-paracyclophanes - Google Patents

Abstract

PURPOSE:To obtain the subject substance in high yield at a low cost by carrying out Hofmann degradation reaction of a paramethylbenzyltrimethylammonium halide derivative in the presence of a polyvinylpyrrolidone catalyst in an aqueous solution containing an alkali metal hydroxide. CONSTITUTION:In synthesizing a compound of formula II by Hofmann degradation reaction of a compound of formula I (X is H, halogen or lower alkyl; (n) is 1-4; Y is halogen) in an aqueous solution containing an alkali metal hydroxide (e.g. 30-40wt.% NaOH aqueous solution), a polyvinylpyrrolidone is used as a catalyst to produce the objective compound in high yield. Especially in case of using an insoluble polyvinylpyrrolidone, separation of the objective compound and recovery of the catalyst can be carried out more readily. A solvent such as toluene or chlorobenzene is preferably used for the reaction. The resultant compound of formula II is useful as an intermediate for production of a coating thin film of a polyparaxylilene.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a (2,2)-variant useful as an intermediate for producing a superficial thin film of polyparaxylylenes by vacuum evaporation in the electronics field. This article relates to a method for producing cyclophanes.

(Prior Art) Conventionally, as a method for producing (2,2)-valacyclophanes, paramethylbenzyltrimethylammonium bromide represented by the formula is treated with silver oxide to produce the corresponding paramethylbenzyltrimethyl hydroxide. Organic 5yn is produced by Hofmann elimination reaction after converting it to ammonium.
theses Ca11. Vol, 5.8331H
However, the yield was as low as 10 to 20%, which was not satisfactory. Also, JP-A-64-45322
In JP-A-63-93740, the Hofmann elimination reaction is carried out using a large amount of an organic solvent and a polar solvent (dimethyl sulfoxide, etc.) for a long period of time. A method of reacting in a solvent has been proposed. However, the use of polar solvents or polyethylene glycol dialkyl ethers may cause the solvent and (2°2)-
It is difficult to separate from valacyclophanes, and since the polar solvent and polyethylene glycol dialkyl ether are water-soluble, it is extremely difficult to recover the solvent after the reaction is completed.
According to additional tests conducted by the present inventors, it was difficult to achieve the desired yield, and the result was not satisfactory for industrial implementation.

(Problems to be Solved by the Invention) The present invention provides a method for industrially producing (2,2)-valacyclophanes using a conventional method using silver oxide, a polar solvent, polyethylene glycol dialkyl ether, etc. The object of the present invention is to provide a method that solves the problems, has simple reaction operations, and produces a target compound in good yield at low cost.

(Means for Solving the Problems) As a result of extensive research into a method for industrially producing (2,2)-valacyclophanes, the present inventors have discovered a halogenated rosemethylbenzyltrimethylammonium derivative [the general The present inventors have completed the present invention by discovering that (2,2) valacyclophanes can be obtained in good yield by the presence of polyvinylpyrrolidone as a catalyst when subjecting Formula (I) to a Hoffmann elimination reaction.

That is, the present invention provides a halogenated compound represented by the general formula (wherein, X represents a hydrogen atom, a halogen atom, or a lower alkyl group, n represents an integer from 1 to 4, and Y represents a halogen atom). A methylbenzyltrimethylammonium derivative is subjected to a Hoffmann elimination reaction in an aqueous solution containing an alkali metal hydroxide,
In producing (2.2)-valacyclophanes represented by the general formula (wherein, X and n have the same meanings as above),
This is a method for producing (2.2)-valacyclophanes, characterized in that the above reaction is carried out in the presence of polyvinylpyrrolidone.

Specific examples of the halogenated rosemethylbenzyltrimethylammonium derivative represented by the above general formula (I) used in the present invention include, for example, rosemethylbenzyltrimethylammonium chloride, 2-chloro-rosemethylbenzyltrimethylammonium chloride, 2-chloro-rosemethylbenzyltrimethylammonium chloride, -Chloro-paramethylbenzyltrimethylammonium bromide, 3-chloro-paramethylbenzyltrimethylammonium chloride, 3-chloro-paramethylbenzyltrimethylammonium bromide, 2(3)-chloro-paramethylbenzyltrimethylammonium chloride (mixture) , 2(3)-chloro-paramethylbenzyltrimethylammonium bromide (mixture), 2,3-dichloro-
Paramethylbenzyltrimethylammonium chloride,
2.5-dichloro-varamethylbenzyltrimethylammonium chloride, 2.6-dichloro-varamethylbenzyltrimethylammonium chloride, 2-promovaramethylbenzyltrimethylammonium chloride, 2
-Promo-baramethylbenzyltrimethylammonium chloride, 3-bromo-baramethylbenzyltrimethylammonium chloride, 3-bromo-baramethylbenzyltrimethylammonium bromide, 2(3)-bromo-baramethylbenzyltrimethylammonium chloride (mixture), 2( 3) -Bromobaramethylbenzyltrimethylammonium bromide (mixture 2.5-dibromobaramethylbenzyltrimethylammonium bromide, 2-fluoro-baramethylbenzyltrimethylammonium chloride, 3-fluoro-baramethylbenzyltrimethylammonium chloride , 2(3)-fluoro-paramethylbenzyltrimethylammonium chloride (mixture), 2,5-difluoro-paramethylbenzyltrimethylammonium bromide, 2,4-dimethylbenzyltrimethylammonium chloride, 3,4-dimethylbenzyltrimethylammonium In addition, halogenated paramethylbenzyltrimethylammonium derivatives can be easily obtained by the method described in JP-A-64-45322, in which benzyl halides and trimethylamine are reacted.

On the other hand, as the polyvinylpyrrolidone that acts as a catalyst, soluble or insoluble polyvinylpyrrolidones can be used. This is cross-1 inked,
Examples include polyvinylpyrrolidones having an average molecular weight of 10,000, an average molecular weight of 24, ooo, an average molecular weight of 40,000, an average molecular weight of 360,000, etc., which are commercially available from Alto Chituri. Furthermore, when cross-linked insoluble polyvinylpyrrolidone is used, the reaction solution and catalyst can be easily separated by filtration after the reaction is completed, and the (2,2)- Cyclophanes are easily obtained, and polyvinylpyrrolidone, which is insoluble in the reaction solvent, can be used again in the reaction after washing with water. Considering post-treatment, it is preferable to use polyvinylpyrrolidone which is insoluble in the solvent.The amount of polyvinylpyrrolidone used is not particularly limited, but is usually 0.1 to 3.0 equivalents (weight) based on the substrate. used. There are no particular restrictions on the form in which polyvinylpyrrolidone is used, but it is usually used in the form of powder.

The reaction solvent may or may not be used, but
Considering recovery of the catalyst, separation of (2,2)-valacyclophanes, etc., its use is preferable. In this case, it is suitable to use a water-insoluble solvent as the reaction solvent. Normally,
Hydrocarbon, halogenated hydrocarbon solvents may be used. For example, toluene, xylene, chlorobenzene, etc. Examples of the alkali metal hydroxide include sodium hydroxide and potassium hydroxide, and the concentration of the aqueous solution thereof is 10 to 50% by weight, preferably 30 to 40% by weight.
Aqueous solutions can be used. There is no limit to the amount of this alkaline aqueous solution used, but - for the compound represented by formula (I),
It is preferable to use 2 to 10 times the amount. In addition, the reaction temperature is
It can be carried out at the boiling point temperature of the solvent from 50°C, but it is usually 70 to 10°C.
Perform at around 0℃.

(Effects of the Invention) According to the present invention, by using polyvinylpyrrolidone as a catalyst, Hofmann An elimination reaction occurs and (2,2)-valacyclophanes are obtained in good yield. In particular, if insoluble polyvinylpyrrolidone is used as a catalyst, the separation of the produced (2.2)-valacyclophanes and the recovery of the catalyst will become easier. This is a method for producing 2,2)-valacyclophanes.

(Example) The present invention will be specifically explained below using Examples.

Example 1 2-chloro-p-xylene was photochlorinated by a conventional method to give 7
The reaction was stopped when 9% of 2-chloro-p-methylbenzyl chloride was produced. 55 g of a 28% trimethylamine aqueous solution was added dropwise to 41 g of this product over 1 hour, and the mixture was further stirred at 60° C. for 5 hours. After cooling, the mixture was extracted with dichloromethane to recover 6.4 g of unreacted 2-chloro-p-xylene.

Under a nitrogen stream, 9Tnll of the aqueous phase (containing about 0.019 mol as monochlorosubstituted rosemethylbenzyltrimethylammonium chloride) was mixed with 30ml of xylene.
．． 85% potassium hydroxide 7.61 parts water 13 parts, insoluble polyvinylpyrrolidone (powder, manufactured by Aldrich: cro
The mixture was added dropwise to a reaction mixture consisting of 5 and 7 g of ss-1 inked) at room temperature with stirring.

The reaction mixture was incubated at 50°C for 1 hour, 70°C for 1 hour, and 95°C.
The mixture was stirred for 6 hours. The reaction solution was filtered while still warm, and the organic phase was separated, washed with water, dried, and then the solvent was distilled off. Dichlorosubstituted (2,,2)-valacyclophane isomer mixture (isomers that differ only in the chlorine substitution position!) 1.34 g (yield: 51
%) was obtained. The GC-MC spectrum of this product matched that of the standard product.

Comparative Example 1 The same reaction as in Example 1 was carried out except that only the insoluble polyvinylpyrrolidone was removed. As a result, 0.76 g (yield: 29
%) of an isomer mixture of dichloro-substituted (2,2)-paracyclophane was obtained.

Comparative Example 2 (A method according to the method described in Example 3 of JP-A No. 63-93740) 5 m [! , 4 g of 85% potassium hydroxide, 7 ml of water, and 12 g of diethylene glycol dimethyl ether was stirred at 95° C. for 10 hours. Post-treatment was carried out in the same manner as in Example 1 to obtain 0.62 g of an isomer mixture of dichloro-substituted (2,2)-valacyclophane (yield 45%).
I got it.

Example 2 3 g of sodium hydroxide, 4.5 g of water, 20 g of xylene,
0.5 g of insoluble polyvinylpyrrolidone as in Example 1
0.01 of monochloro-substituted rosemethylbenzyltrimethylammonium chloride was added to a reaction mixture consisting of
Five drops of an aqueous solution containing mol were added dropwise at room temperature. The temperature was raised sequentially, and the mixture was stirred at 45°C for 1 hour, at 60°C for 1 hour, and at 75°C for 20 hours. The reaction solution was filtered while it was still warm, and the solid matter was washed with 50 ml of hot toluene. After separating the aqueous phase, the organic phase was washed with water and dried over anhydrous sodium sulfate. When the solvent is distilled off (
0.84 g of powder crystals of 2,2)-paracyclophane (
A yield of 60%) was obtained.

Example 3 In Example 2, 0.5 g of water-soluble polyvinyl pyrrolidone (shaped powder) [manufactured by Aldrich Co., Ltd., average molecular weight 40,000] was used instead of insoluble polyvinyl pyrrolidone, and 70
The mixture was stirred at ℃ for 20 hours.

After separating the aqueous phase, the organic phase was washed with water and dried over anhydrous sodium sulfate. When the solvent was distilled off, 0.99 g (yield 71%) of powder crystals of (2,2)-valacyclophane was obtained.

Example 4 A reaction mixture consisting of 6 g of potassium hydroxide, 7 g of water, 40 ml of xylene, and 3 g of the same insoluble polyvinylpyrrolidone as in Example 1 was mixed with 51 Tl of an aqueous solution containing 0.011 mol of rosemethylbenzyltrimethylammonium chloride.
ii was added at room temperature and stirred at 95°C for 7 hours. Example 1
After treatment in the same manner as (2,2)-paracyclophane 0.
38 g (yield 32%) was obtained. GC-MS of this thing
The spectrum matched that of the standard product.

Comparative Example 3 When the reaction of Example 4 was carried out without the insoluble polyvinylpyrrolidone, only 6 g (yield 5%) of (2°-valacyclophane) was obtained.

Patent Applicant Ihara Chemical Industry Co., Ltd. Agent Patent Attorney Ii 1) Toshi Sanzo Rokuyo L Bee

Claims (1)

[Claims] There are general formulas, ▲mathematical formulas, chemical formulas, tables, etc.▼...(I) (wherein, (Y represents an integer and Y represents a halogen atom) is subjected to a Hofmann elimination reaction in an aqueous solution containing an alkali metal hydroxide, and the general formula ▲mathematical formula , chemical formulas, tables, etc.▼・・・(II) (In the formula, X and n have the same meanings as above.) (2
, 2) A method for producing (2,2)-paracyclophanes, characterized in that the above reaction is carried out in the presence of polyvinylpyrrolidone.