METHOD OF PREPARING OF ARTHROPODICIDAL OXADIAZINE INTERMEDIATE

The present invention pertains to a process for preparing of methyl chloroformyl[4-(trifluoromethoxy)phenyl]carbamate of formula I as intermediate in the preparation of arthropodicidal indoxacarb, comprising reaction of compound of formula (IV) with phosgene or phosgene derivative in the presence of phase transfer catalyst, alkaline base and hydrocarbon organic solvent and in the absence of organic base and metal hydride. This invention also pertains to a telescopic process for preparation of methyl chloroformyl[4-(trifluoromethoxy)phenyl]carbamate of formula I comprising preparation of isocyanate of formula (II) by reaction of compound of aniline derivative of formula (III) with phosgene or phosgene derivative in the presence of dimethylcarbonate and hydrocarbon organic solvent; following the preparation of compound of formula (IV) by reaction of compound of formula (II) with methanol and distillation out of dimethylcarbonate and reaction of compound of formula (IV) with phosgene or phosgene derivative in the presence of phase transfer catalyst, alkaline base and hydrocarbon organic solvent.