Method for synthesizing phenyl carbamate

Abstract

The invention relates to a method for synthesizing phenyl carbamate and the method uses selenium as catalyst, organic base as cocatalyst and aniline and alcohol as reactants. The method comprises the step of performing an oxidative carbonylation reaction under carbon monoxide and oxygen in an autoclave to obtain phenyl carbamate. The invention has simple process, easy operation, high atom economy, environmental friend, cheap and accessible raw materials and catalyst, low cost and high yield, the product is easy to separate and purify, the catalyst is easy to separate and reclaim and can be recycled.

Description

technical field [0001] The invention relates to a method for synthesizing phenylcarbamate. Specifically, under the catalysis of selenium, the oxidative carbonylation reaction of aniline and alcohol with carbon dioxide and oxygen in a closed autoclave provides a method for the synthesis of phenylcarbamate with short steps, convenient operation, and environmental friendliness. Inexpensive new method. Background technique [0002] 4,4'-diphenylmethane diisocyanate (diphenylmethane-4,4'-diisocyanate, referred to as MDI) is one of the most important raw materials for the preparation of polyurethane. Polyurethane is a new type of polymer material. As one of the six most promising synthetic materials in the world, it has the dual advantages of rubber and plastic, and has the advantages of wear resistance, oil resistance, low temperature resistance, high temperature resistance, corrosion resistance, radiation resistance, Incomparable advantages of other synthetic materials such as...

AI Technical Summary

Problems solved by technology

Its disadvantage is that noble metals or their complexes are used as catalysts, and the catalysts are expensive and complicated, which greatly increases the reaction cost.

The disadvantage is that the catalytic system used is relatively complex, the reaction usually needs to be carried out under anhydrous conditions, the operating conditions are relatively harsh, the atom economy is low, there are many side reactions, and the post-treatment is relatively cumbersome.

However, along with the generation of the target product, there is always an equivalent amount of by-product aniline to generate, which leads to low atom economy of the reaction, and increases the difficulty of separation and purification of the main product. In addition, diphenylurea is used as the starting material, which increases the response cost

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