SYNTHESIS OF HIGH-PURITY TRIAZOLE THIOKETONE FUNGICIDE PROTHIOCONAZOLE
Using 1-(1-chlorocyclopropyl)ethanone as the raw material,2-(1-chlorocyclopropane)-3-chloro-1-(2-chlorophenyl)-2-propanol was prepared through chlorination and Grignard reaction.It reacts with 1,2,4-triazole under alkaline conditions to obtain 2-(1-chlorocyclopropane)-3-(1,2,4-triazole-1-yl)-1-(2-chlorophenyl)-2-propanol.Finally,it reacted with sulfur by electrophilic addition reactionto obtain the target product.The product was identified by 1H NMR and its structure is consistent with that of prothioconazole.This process is easy to operate and solves the problem of position selectivity in the introduction of 1,2,4-triazole.The yield of this reaction step is increased to 59.8%,which is suitable for industrial production.