SU391124A1 - METHOD OF OBTAINING SPATIALLY DIFFICULT HEXAFENOLS - Google Patents

Description

one

The invention relates to the chemical industry of the national economy, to the production of high molecular weight polyphenols containing sterically hindered hydroxyl groups, which can be used as inhibitors of the oxidation of polyolefins.

The proposed method, based on the known phenyl alcohol alkylation reaction, allows to obtain compounds not described in the literature.

Bisphenols with four free reaction centers were used for the first time as starting phenols. Consequently, it was possible to anticipate the formation of a mixture of mono-, DI-, tri- and tetraalkylated products. According to the proposed method, 4 molecules of an alkylating agent are attached to 1 molecule of bisphenol and individual tetrasubstituted products are formed. The method consists in alkylation of alkylene-, thio- or dithio-bisphenols 3,5-di-treg-butyl-4-hydroxybenzyl alcohol in a molar ratio of 1: 4 in the presence of an acidic catalyst, for example -toluene-sulphonic acid, in an organic solvent at the boiling point of the reaction mass with the subsequent selection of the target product by known techniques.

1 mol of the starting bispheiol, for example 4,4-thio-bisphenol, and 4 mol of 3.5 di-greg-butyl-4-oxybepzyl alcohol are dissolved in a suitable organic solvent, for example in benzene, a catalytic amount of catalyst, for example p-toluenesulfonic acid, is added and boiled t until the separation of the reaction water in the trap. The reaction mass is filtered off in alcohol, for example ethanol, and poured dropwise into cold water with vigorous stirring. The precipitated powdery precipitate is filtered and dried at 60 ° C, then in a vacuum desiccator over P2O5. The yield of reaction products 85-90% of theoretical.

Synthesized compounds are from white to light yellow powders.

colors soluble in most organic solvents. They are characterized by elemental analysis, IR spectroscopy, molecular weight. In the IR spectra of the compounds obtained, there are characteristic absorption bands at 3650 s. (OH) and 3530 cm-1 (spatially obstructed by the OH group).

The compounds obtained have better properties than similar compounds.

Example 1. Getting 2,2,6, C-tetra (3,5-ditert-butyl-4-hydroxybenzyl) diphenylolpropane.

2.28 g (0.01 g-mol) of diphenylol-propane and 9.55 g (0.04 g-mol) of 3,5-di-greg-butyl-4-hydroxybenzyl alcohol are dissolved with heating and stirred in 50 ml of benzene. and a catalytic amount of rt-toluenesulfonic acid is added to the solution. The reaction mass was thrown in until the reaction water was separated in the trap, after which it was filtered from the catalyst and the benzene was distilled off. The residue, on standing, solidifies into a brittle resin, which is dissolved at room temperature in ethanol, and is poured, but dropwise, with vigorous stirring, into water. The precipitate was filtered off and dried at 60 ° C, then in a vacuum desiccator over P20s. Obtain 9.9 g (90% of theoretical) of the light cream powder with t. Nl. 92-94 ° C.

Found,%: C 80.91; H 9.62; a pier at. 1055.

C75H104Ob.

Calculated,%: C 81.76; H 9.51; a pier at. 1101.

Example 2. Obtaining 2,2,6,6-tetra- (3,5di-tert-butyl-4-hydroxybenzyl) -4,4thio-bisphenol.

The compound is prepared as described in Nimer 1, starting from 8.72 g (0.04 g-mol 4.4-thiobisphenol and 37.76 g (0.16 g-mol} 3.5-di-tert-butyl-4- hydroxybenzyl alcohol. The final product is a light yellow powder with mp 82-84 ° C, yield 40.0 g (91% of the theoretical).

Found,%: C 79.34; H 9.18; S 3.13; a pier at. 1037.

SrgNdVZob

Calculated,%; C 79.21; H 9.05; S 2.93; a pier at. 1091.

EXAMPLE 3. Preparation of 2,2,6,6-tetra (3,5-diGuSeg-butyl-4-hydroxybenzyl-4, 4-dithiobisphenol.

The compound was prepared as described in example 1, starting from 2.5 g (0.01 gmol of 4,4-dithiobisphenol and 9.44 g (0.04 gmol of 3,5-digreg-butyl-4-hydroxybenzyl alcohol. 9.6 g (85% of theoretical) of a white powder with mp 85-87 ° C is formed.

Found,%: C 76.80; H 8.61; S 5.45; a pier at. 1136.

C72H9852About

Calculated,%: C, 76.96; H 8.61; S 5.70; a pier at. 1123.

Subject invention

1. A method for preparing hindered hexaphenols characterized in

that alkylene-, thio-, or dithio-bisphenols are reacted with 3,5-di-7-butyl-4-hydroxybenzyl alcohol in the presence of an acidic catalyst, for example, α-toluene sulfonic acid, in an organic solvent at the boiling point of the reaction mass, followed by isolation of the target product by known methods .

2. A process according to H. 1, characterized in that the process is carried out at a molar ratio of the starting bisphenol and 3,5-di-tert-butyl-4-hydroxybenzyl alcohol, equal to 1: 4.