Method for preparing toluene diamino butyl formate

Abstract

The invention relates to a method for preparing toluene diamino butyl formate, which comprises the following steps: adding toluene diamine, urea, butanols and a catalyst in a reaction vessel, wherein the mol ratio of the reaction components is characterized in that toluene diamine to urea to butanols is 1:2-10:10-90, and the catalyst amount accounts for 5%-60% of mass of toluene diamine, sealing the reaction vessel after charging, under the stirring condition, heating to the temperature of 130-250 DEG C for reacting for 1-10 hours, cooling after finishing the reaction, discharging, filtering and separating the catalyst at the temperature of 30-90 DEG C to obtain the products toluene diamino butyl formate. No material addition and removal is provided during the reaction period, the operation is convenient by only requiring reaction temperature control; the reaction condition is mild; the used catalyst has the advantages of low price, high catalytic activity and high yield of the product as high as 81.8%; the catalyst and the reacted material are easy to be separated, the catalyst enables no deactivation and good repetitive usability.

Description

technical field [0001] The invention belongs to a method for preparing phenylcarbamate by urea catalytic reaction, in particular to a method for preparing butyl toluene dicarbamate by catalytic reaction of toluene diamine, urea and butanol. Background technique [0002] Toluene dicarbamate is an important organic compound, which can be used as pesticide and medicine, more importantly, as an intermediate for the synthesis of toluene diisocyanate (TDI), and toluene diisocyanate is an important raw material for the preparation of polyurethane. The traditional TDI production adopts the phosgene method, which has disadvantages such as the highly toxic raw material phosgene, the corrosion of equipment by the by-product hydrochloric acid, and the difficulty in removing residual chlorine in the product. At present, the non-phosgene route has become the focus of domestic and foreign researchers, and various non-phosgene synthesis methods for TDI have been reported in a large number o...

AI Technical Summary

Problems solved by technology

[0006] In the above-mentioned existing literature reports that directly utilize toluene diamine, urea and butanol to synthesize butyl toluene dicarbamate, a multi-stage reaction is adopted, the catalyst used is not environmentally friendly, the catalyst is easily deactivated when exposed to the environment, or the catalyst is used as a liquid As a catalyst, it is difficult to separate from the reaction system

Moreover, in the previous literature reports, the deactivation and reusability of the catalyst have never been involved, and the reusability of the catalyst is an unavoidable problem in the actual process of production, which directly affects the production cost

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