A process for the preparation of 4-subsrituted benzopyran derivatives which comprises preparing N-(2-cyanoethyl)-5-fluoro-4-fluoromethyl-4-(4-trifluoromethylphenoxy)-2-pentynamide from 1-fluoro-2-fluoromethyl-3-butyn-2-yl 4-trifluoromethylphenyl ether and cyclizing this pentynamide derivative into 2,2-bis(fluoromethyl)-N-(2-cyanoethyl)-6-trifluoromethyl-2H-1-benzopyran-4-carboxamide; and other processes therefor. The processes make it possible to prepare the benzopyran derivatives in a shortened process time as compared with those of the prior art with high safety through easy purification.
一种制备 4-亚
硫酰
苯并呋喃衍
生物的工艺,包括从 1-
氟-2-
氟甲基-3-丁炔-2-基 4-三
氟甲基苯基醚制备 N-(2-
氰乙基)-5-
氟-4-
氟甲基-4-(4-三
氟甲基苯氧基)-
2-戊炔酰胺,并将该戊炔酰胺衍
生物环化为 2、2-双(
氟甲基)-N-(2-
氰乙基)-6-三
氟甲基-2H-1-苯并
吡喃-4-甲酰胺;及其他工艺。与现有技术相比,这些工艺可以在更短的时间内制备苯并
吡喃衍
生物,而且易于纯化,安全性高。