SU427006A1 - METHOD OF OBTAINING SUBSTITUTED DIOXANES-1,3 - Google Patents

Description

one

The invention relates to a method for producing new compounds - substituted dioxanes1, 3 of the general formula

, R CH; HE

r4-CH-f a. 1 R,

where R is hydrogen or halo, alkyl or aryl; R and R2 - hydrogen, alkyl, aryl or cycloalkyl, which can be used in the production of antioxidants, additives for fuels, oils, rubbers, fats, phenol-formaldehyde resins, bactericides, etc.

The proposed method is based on the known reaction of obtaining substituted phenols by alkylation of phenols with olefies in the presence of acidic catalysts, and consists in the fact that dioxane-1,3 of the general formula

R

R

.

where R is as defined above, is treated with a phenol of the general formula

HE

,

RO

where RI and R2 are as indicated above, when heated in the presence of an acidic catalyst, preferably in a solvent medium, and the

The target product is in the form of a mixture of isomers or is divided into individual isomers by conventional methods.

Acids such as sulfuric acid, phosphorus, and ion exchange resins can be used as the acid catalyst.

Vinyl-based precursors of dioxanes-1,3 can be obtained by condensation of diolefins, such as divinyl, isoprene, phenoprene,

chloroprene, 4-vinylcyclohexen-1, vinyl norbornene, with formaldehyde in the presence of acidic homogeneous and heterogeneous catalysts. Conversion of dioxane-1,3 is 70%.

The output of monosubstituted in the "position of the phenol is 45-50%, the yield of the o-isomer is 5-10%. The rest is the products of polymerization and compaction of the starting dioxane-1,3. Phenol ethers are not formed.

.. "Jf

 276; Example. A mixture of 68 g (1 mol) of isoprene, 60 g (2 mol) of 36% solutionformalin and 25 g of KU-2 cation-exchange resin is loaded into the reactor and stirred for 4-5 hours at 40-45 ° C, the catalyst is filtered, the reaction products extracted with benzene, the solvent and unreacted isoprene are distilled off, and after vacuum distillation, 4-methyl-4-vinyldioxane-1,3, t. bale is obtained. 153-154 ° C. The output of 55-60% converted to isoprene. Conversion of isoprene 50-60%. For 1 mol of 4-methyl-4-vinyldioxane-1,3, 2-6 mol of phenol are taken and the reaction is carried out at 100-130 ° C for 8-10 hours in the presence of 20-50% cation exchange resin based on the amount of the initial dioxane. At the end of the reaction, the catalyst, the excess phenol are separated, and the unreacted dioxane is distilled off and a fraction of m.p. 125-147 ° C / 10 mm, easily crystallized on standing. Mol weight (cryoscopy in benzene) 216 (calculated 222). According to IR spectroscopy (absorption bands at 755 and 830), this fraction is a mixture of o- and p-substituted phenol isomers. After recrystallization from carbon tetrachloride, 4-methyl-4-a- (-oxyphenyl) -ethyl dioxane was isolated, m.p. 78-80 ° C, yield 45-50%. Found,%: C 70.05; H 7.97; OH 7.5 (according to Verleu). G M About Calculated,%: C 70.3; H 8.13; OH 7.8. IR spectrum, 830 (-substituted benzenes), 1200-900 (C-O-C-O-C), 3400 w. (OH), 1373 (CH3). The o-isomer was not isolated.

ff g I, .1

ii. Subject of the invention 1. A method for producing substituted dioxans-1, 3 of the general formula n-i. H where R is hydrogen or halo, alkyl or aryl; RI and Kr are hydrogen, alkyl, aryl or cycloalkyl, characterized in that dioxane-1,3 of the general formula, where R has the above values, is reacted with a phenol of the general formula where Ri and R2 are as indicated above, when heated in the presence of an acidic catalyst and isolate the desired product as a mixture of isomers or divide it into individual isomers by conventional methods, 2. The method of claim 1, wherein the reaction is carried out in a solvent medium.