DE940044C - Process for the preparation of anthranyl vinyl ethers - Google Patents

Description

Process for the preparation of anthranyl vinyl ethers It is known that one phenols with acetylene in the presence of alkaline catalysts can convert to aryl vinyl ethers. If, on the other hand, phenols are treated with acetylene in liquid phase using zinc or cadmium salts as catalysts, this is how polyoxystyrenes are obtained.

It has now been found, surprisingly, that anthrone and acetylene in the presence of compounds of zinc or cadmium at elevated temperatures can react in good yield to the vinyl ether of anthranol- (9). Instead of the anthrone one can also use the anthranol- (9) tautomeric with it or its substitution products.

The reaction is carried out in an inert solvent such as benzene, toluene, xylene. The most favorable reaction temperatures are between roo and 300 °, preferably from 17o to Zoo '. Zinc and cadmium compounds that are largely soluble in the reaction mixture have proven particularly useful as catalysts. are e.g. B. the stearates, naphthenates or acetates of zinc or cadmium.

The process can be carried out both at normal pressure and under increased pressure Printing can be carried out. It is expedient to work up the reaction mixture any solvent used is distilled off and then the formed Anthranyl vinyl ether distilled over in vacuo. The still liquid distillate becomes freed from small amounts of impurities precipitating in crystalline form and then cooled, whereby the anthranyl vinyl ether is in the form of yellow crystals separates: The anthranyl vinyl ether can be used as an intermediate, z. B. for the Manufacture of plastics, use.

The parts given in the example below are parts by weight. Example i 300 parts of anthrone are suspended in 1600 parts of toluene and 30 parts Zinc stearate added. The mixture is then in a stirred autoclave at i8o to igo ° with a mixture of nitrogen and acetylene with a volume ratio of i: 3 at a pressure of 20 to 25 atm. treated. The acetylene consumed is through Repressing fresh acetylene replaced. After taking the calculated amount of acetylene it is allowed to cool and the toluene is distilled from the filtered reaction mixture away. The residue is then subjected to distillation under reduced pressure, the fraction passing over between 175 and 185 ° 4 Torr being the anthranyl vinyl ether Contains in yields of 75 to 8o% of the theoretical amount. The liquid distillate is made up of small amounts of precipitated crystals, which are essentially dianthrone next to some anthrone and anthraquinone represent, sucked off. Obtained from the filtrate by inoculating with cooling the anthranyl vinyl ether in yellow crystals which Melting at 47 '. Example e In a stirring autoclave made of stainless steel, 400 parts are made Anthrone, 2500 parts of toluene and 40 parts of dry zinc acetate were poured in. After this Flushing the autioclave with nitrogen will be 5 atm. Nitrogen and 10 atm. acetylene pressed on. The autoclave is now heated to between 170 and 180 ° with thorough stirring. That Used acetylene is replenished by continuously pressing in fresh acetylene. The reaction is complete in the course of about 60 hours.

The pressure in the autoclave is released after cooling, and the toluene is distilled off and the reaction mixture was taken up with ether. The anthrone excreted here is filtered off, washed with ether and dried. It will be about 75 parts Anthron recovered. The ethereal filtrate becomes after driving off the ether distilled in vacuo, with 23o parts of a distillate of Kpl, o 162, to z78 ° are obtained with an anthranyl vinyl ether content of 75%. As a residue igo parts of a resinous product remain. The cleaning is carried out as in the example i.

EXAMPLE 3 In a Sehüttäutoklav an S, usperasion of 40 parts of anthrone and 3 parts of cadmium stearate in 60 parts of toluene at 180 to 200 ° with a mixture of nitrogen and acetylene by volume ratio. i: 3-at, a pressure of 2o to 25 atm. treated. That consumed. Acetylene is replaced by injecting fresh acetylene. When the uptake is complete, the toluene becomes. distilled off from the mixture and the residue was subjected to distillation under reduced pressure. The fraction passing over between 175 and 185 ° at 4 doors contains the anthranyl vinyl ether in yields of 50 to 75% of theory. The cleaning takes place as in example i. Example 4 300 parts of anthranol- (9), as it is, for. B. can be obtained by acidifying an alkali anthranolate solution, suspended in 1,600 parts of toluene and, after adding 3o parts of zinc stearate, in a stirred autoclave at i8o to igo ° with a mixture of nitrogen and acetylene in a volume ratio of i: 3 at a pressure of 2o to 25 Atm. treated. The acetylene used is replaced by pressing in fresh acetylene. After the calculated amount of acetylene has been taken up, the mixture is allowed to cool and the reaction mixture is worked up in the manner described in Example i. The anthranyl vinyl ether is obtained in yields of 75 to 80% of the theoretical amount. Example .5 333 parts of 1,4-dimethylanthrone are suspended in 700 parts of toluene, 3o parts of zinc stearate are added and the mixture is placed in a stirred autoclave at iSo ° with a mixture of nitrogen and acetylene in a volume ratio of i: 3 at a pressure of 2o to 25 atm . treated. The acetylene used is replaced by pressing in fresh acetylene. After the calculated amount of acetylene has been taken up, the mixture is allowed to cool and the solvent is distilled off after a dark-colored solid has been filtered off from the mixture. The residue is then subjected to distillation under reduced pressure. At 16o to igo ° and 4 Torr goes. a fraction above which contains the (1,4-dimethylanthranyl) vinyl ether.

Claims (1)

PATENT CLAIM: Process for the production of anthranyl vinyl ethers, characterized in that one anthrone or anthranol (9) or their substitution products with acetylene in the presence of zinc or cadmium compounds and of indifferent ones Reacts solvents at elevated temperatures.