苯嘧磺草胺的新合成方法

New Synthetic Method of Saflufenacil

设计并完成苯嘧磺草胺及其关键中间体的合成工艺路线,使其具备工业化生产潜力。采用氯磺酰异氰酸酯、叔丁醇、N-异丙基甲胺等作为起始原料,制备了关键中间体N-甲基-N-异丙基氨基磺酰胺,3步反应总收率约75%。再以2-氯-4-氟苯甲酸为原料,经过硝化、酰氯化、缩合、催化氢化还原、氨酯交换、甲基化反应制备了苯嘧磺草胺。8步反应的总收率为48. 6%,纯度98. 6%,产物与中间体经NMR、MS等确证。

The synthetic process of saflufenacil and its key intermediates is designed and completed,which has the potential for industrial manufacturing.The key intermediate N-methyl-N-isopropylaminosulfonamide is prepared by using chlorosulfonyl isocyanate,t-butanol,N-methyl-N-isopropylamine as the starting material.The overall yield of the three-step reaction is about 75%.Then,2-chloro-4-fluorobenzoic acid was used as a raw material to prepare saflufenacil by nitration,chloridization,condensation,catalytic hydrogenation reduction,aminolysis and methylation reactions.The total yield of 8 steps is 48.6%,and the purity of the target product is 98.6%.The final products and the intermediates are characterized by NMR and MS.