There is described a process for the preparation of a compound of formula I ##STR1## in which process: a) a compound of formula II ##STR2## is reacted with an organolithium compound of formula III Li--R.sub.7 (III) b) the resulting lithium complex is reacted with a compound of formula IV Y.sub.1 --CO--CO--Y.sub.1 IV to form a compound of formula V ##STR3## c) that compound is, in either order, c1) oximated with O-methylhydroxylamine; or oximated with hydroxylamine and then methylated or fluoromethylated or difluoromethylated; c2) reacted with a chloroformic acid ester. X, m, Y, R.sub.1 to R.sub.3 and R.sub.7 are as defined in the description.
描述了一种制备I式化合物的过程 ##STR1## 在该过程中: a) 用II式化合物 ##STR2## 与III式
有机锂化合物 Li--R.sub.7 (III) 反应 b) 用IV式化合物 Y.sub.1 --CO--CO--Y.sub.1 IV 与所得的
锂络合物反应形成V式化合物 ##STR3## c) 以任意顺序,将该化合物进行以下反应: c1) 与O-甲氧基
羟胺氧化;或先与
羟胺氧化再甲基化或
氟甲基化或二
氟甲基化; c2) 与
氯甲酸酯反应。其中X,m,Y,R.sub.1至R.sub.3和R.sub.7如描述中所定义。