SU92622A1 - The method of producing esters and ketones from primary alcohols by catalytic dehydrogenation condensation - Google Patents

Description

It is known to obtain esters from primary alcohols using a copper oxide-activated thorium catalyst. However, this produces low yields.

It is also known to produce ketones from primary alcohols at 450 ° using a chromium catalyst with outputs of 30-60Vo.

The proposed method for the preparation of esters or ketones from primary alcohols by catalytic dehydrogenation condensation makes it possible to obtain higher yields of esters and ketones than in the known methods with the possibility of carrying out both these processes on the same catalyst and in the same hardware.

A distinctive feature of the method is that the alcohols in the current of the hydrogen are carried out over a copper catalyst activated by the addition of thorium oxide at temperatures up to 360 ° to obtain esters and at temperatures above 300 ° to obtain ketones.

Example 1. Above a copper catalyst containing thorium oxide containing 5Vo, ethanol vapor is passed at 250–260 ° and about. with. 200-250 in a stream of hydrogen, when the ratio of alcohol and hydrogen. /. The condensate formed (about 90 g out of 100 g alcohol) consists of 9-11 / o acetic aldehyde 40-43Vo ethyl acetate, 9-UVo acetone and 4-5Vo free acetic acid. The fraction with a boiling point of 78-79 °, which is pure acetic ethyl ether, is isolated by distillation on a column (after infusion with calcium chloride). The ether yield is 42-45Vo from the theoretically possible. When the reaction temperature rises to 325-330, while maintaining other conditions constant, from 100 2 alcohol 50Vo condensate is formed, containing up to ethyl acetate, 60Vo acetone and traces of acetaldehyde. Pure acetone is isolated by distillation with a yield of up to 70-75Vo from the theoretically possible.

JMo 92622

Example 2. Butyl alcohol in a mixture with hydrogen is passed through a catalyst with a temperature of 275 ° and about. with. 150. From 100 g of alcohol, 80 g of condensate containing aldehyde oil, 13Vo dipropyl ketone and 36IVo wt l butbutyl ether are obtained. A fraction with a boiling point of 163-166 °, representing pure butyl butyl ether, is obtained by distillation to yield from theoretically possible. In the same conditions, but at-325 ° and on. with. 180 out of 100 g of butyl alcohol get 75 g of condensate of the following composition: oil aldehyde, approximately 6Vo of butyl ether, and 46-48Vo of dipropyl ketone. The latter during fractionation goes at 142-145 °. The resulting fraction contains 85-90Vo dipropyl ketone, which is 87-QOVo from the theoretically possible.

Example 3. 100 g of primary isoamyl alcohol by passing with hydrogen over a catalyst at 280-300 ° and about. with. 150 form 85 g of condensate containing 50-55 / o isoamyl isomerized ether. By distillation on the column, the fraction with m.p. 189-192 ° representing pure ether. The output of the latter is from theoretically possible. Under the same conditions, but at a temperature of 400-405 ° out of 100 g of isoamyl alcohol, 80 g of condensate containing 45-47- ./o diisobutyl ketone are obtained, which, after fractionation, is obtained in pure form with a yield of 70-BQVo from theoretically the possible.

Subject invention

The method of producing esters or ketones from primary alcohols 10B by catalytic dehydrogenation condensation, characterized in that the alcohols in a stream of hydrogen are conducted over a copper catalyst, activated by adding thorium oxide, at temperatures up to 300 ° to obtain esters and at temperatures higher than 300 ° to obtain ketones.