SU247936A1 - Method of producing monoallylidenepentaerythritol - Google Patents

Description

This invention relates to the field of obtaining a new raw material for the production of plastics, Monoallschidenpentaerythritol - pentaerythritol niuacetal pentaerythritol is a trifunctional compound - glycol with allyl: a double bond. Such glycol can be widely used as a new raw material for the synthesis of various polyester resins, as well as their modifications.

A known method for producing monoallylidenepentaerythritol by reacting pentaerythritol with an acroleip excess at boiling in the presence of p-toluenesulfonic acid. The yield of the target product is 32.6%.

The proposed method for producing monoallylidenepentaerythritol differs from the known method in that sodium bisulfate or hydrochloric acid is used as a catalyst and the process is carried out in an aqueous medium at.

Example 1. A 56 pound flask, 6.8 g, 200 ml of water, 0.08 g (0.007 mol) was charged into a n-pigorna flask spabzhenpyu stirrer, reversible refrigerator, dropping funnel, thermometer and tube for iodachi nitrogen, load 136 g (1 mol) of pentaerythritol hydrohypopa. The mixture is heated to 25-30 ° C with stirring under a stream of nitrogen and 84 g (1.37 mol) of 92% -rolinea are added from a dropping funnel over a period of 2 hours, and the temperature is maintained at a temperature of 3 hours. Upon completion of the reaction, the mixture is neutralized with soda to a pH of 7-8 and water is distilled off with a residual pressure of 150–160 mm Hg. Art. For the final dehydration of the reaction mixture, an azeotroin distillation of water with benzene is carried out. From the benzene solution, clear crystals of mono-allylidene and azritrite fall out of the cooling.

The crystals are filtered off and the pas (|) filter is washed with cold benzene.

The resulting as a by-product of the reaction is neptaerythritol acetyl acetal — diallylidenepentaerythritol remains in the benzene form.

For purification, the resulting crystals were yerscrystallized from benzene in a ratio of 1:10 with the addition of 0.5% by weight of timber of activated carbon. HRD-104.4 g of the purified substance is isolated (57-60% of the theoretical, considering nenaerythritol).

Moleallidepentaerythrinth is a slightly yellow-colored, shiny crystals that are readily soluble in water, alcohol, acetone, and insoluble in aromatic and chlorinated hydrocarbons.

The package has the following konteity: t. Il. 80 ° С, content of OH-grounds is 19.6-19.3; bromine number 89.5-89,6.

Found,%: C 54.92; H 55.08, 7.9, 7.93.

For C8Hi4O4, monoallylidenepentaerythritol is calculated,%:

OH 19.54; bromine number 92.

C 55.17; 8.05.

Example. 2. The experiment was carried out as described in Example 1, but hydrochloric acid was used as a catalyst.

The yield of monoallylidenepentaerythritol is 45-50% of the theoretical.

Example 3. The experiment was carried out as described in Example 1, but using -toluenesulfonic acid as the catalyst. The yield of monoallylidenepentaerythritol is 45-50% of the theoretical.

Example 4. The experiment was carried out as described in Example 1. But the reaction was carried out at 2-5 ° C. The output of monoallylidenepentaerythritol 35% of theoretical.

PRI me R 5. The experiment was carried out as described in Example 1, but the reaction was carried out in dimethylformamide-water (1: 1). Output monoallylpdennentaerythritol - up to 60%

Subject invention

The method of obtaining monoallylidenepentaerythritol by the interaction of pentaerythritol with acrolein in the presence of an acid catalyst and an extract and the target product, characterized in that, in order to increase the yield of the target product, sodium bisulfate or hydrochloric acid is used as a catalyst and the process is carried out in an aqueous medium at 2- 30 ° C.