Method for preparing intermediate of uracil compound containing isoxazoline

Abstract

A method for preparing an intermediate of a uracil compound containing isooxazoline includes the steps of: making 3-amino-4,4,4-trifluorocrotonic acid methyl ester react with substituted aryl carbamate; in a reaction process, continuously evaporating water and byproduct alcohol in the system; and conducting processing to obtain the intermediate of the uracil compound containing isooxazoline. Using this method the selectivity of the reaction and the utilization rate of raw materials are improved; the hydrolysis products, impurities and tar are reduced; the reaction time is greatly shortened; and the productivity is improved. After one recrystallization of crude products, an intermediate product with purity of more than 97% can be obtained, and quantitative yield can be more than 85%.