A process for producing compounds of formula (VIIa) and (VIIb) wherein X is a leaving group; Y and Y
1
are idependently Cl or Br; and Z is Cl, Br or a haloalkyl group which process comprises a) reacting a compound of formula (VII) wherein X, Y, Y
1
and Z are as defined for compounds (VIIa) and (VIIb) with a substantially optically pure chiral amine in a solvent to form a diastereoisomeric salt; b) separating the diastereomeric salt of each enantiomer; c) converting the diastercomeric salt of each anantiomer separately to compounds of formulae (VIIa) and (VIIb) respectively by acid or base hydrolysis, the use of the compounds in making pyrethroid insecticides and novel intermediates.
一种制备式(VIIa)和(VIIb)化合物的方法,其中X是一个离去基团;Y和Y1分别是Cl或Br;Z是Cl,Br或卤代烷基,该方法包括:a)在溶剂中用近乎光学纯的手性胺与式(VII)化合物反应,其中X,Y,Y1和Z的定义与化合物(VIIa)和(VIIb)相同,形成对映异构体盐;b)分离每个对映异构体盐;c)通过酸或碱
水解分别将每个对映异构体盐转化为式(VIIa)和(VIIb)化合物,其中该化合物用于制造拟
除虫菊酯类杀虫剂和新型中间体。