Produce methods of tetraethyl Michaelis ketone
Source: | Author:demihind | Publish time: 2020-11-23 | 115 Views | Share:
Produce methods of tetraethyl Michaelis ketone
The main preparation methods of tetraethyl Michaelis ketone are as follows:

1. Condensation of N, N-diethylaniline and phosgene
In the first step, phosgene condenses with N, N-diethylaniline to form p-diethylaminobenzoyl chloride. Then, in the presence of zinc chloride, it reacts with another molecule of N, N-diethylaniline to form 4,4 '- bis (diethylamino) benzophenone, accompanied by the formation of 2,4' and 2,2 'isomers.
In this process, N, N-diethylaniline was used as raw material to react with phosgene. A large amount of aluminum chloride was used as catalyst. The yield of the reaction was 60% ~ 70%. There was a large amount of sewage discharged. The use of highly toxic gas phosgene put forward high requirements for equipment and operation, and the content of the product was only about 90%.

2.The production of tetraethyl ketone

The oxidation process is a two-step process to produce tetramethylmichaelone and tetraethylmichaelone. In the first step, 4,4 '- bis (dialkylamino) diphenylmethane was obtained by the reaction of N, N-dialkylamine with formaldehyde and p-aminophenyliodate as catalyst at 80 ~ 90 ℃ for several hours. The yield was 95%. The second step is to dissolve 4,4 '- bis (dialkylamino) diphenylmethane in hot ethanol. In the presence of cobalt complex catalyst, the reaction is carried out at 50 ~ 60 ℃ for several hours. The yield of tetraethylmichaelone is 85%. The purity of the product can reach over 96%, and the content can reach 98.5% after being refined with activated carbon and ethanol.