New substituted 3-isocyanate-1,2,5-oxadiazoles

PURPOSE: To provide new 3-isocyanate-1,2,5-oxadiazole having a substd. group in 4-position, extremely useful as raw materials for producing furazane system insecticides or miticides. CONSTITUTION: The objective compds. are expressed by formula I (where R is a phenyl which may be occasionally substd. by halogen, NO 2 , CN, alkyl, alkoxy, alkylthio, halogeno-alkyl, alkylcarbonyl, alkoxycarbonyl or the like), e.g. 4-(4-chloro-phenyl)-3-isocyanate-1,2,5-oxadiazole. The compds. are obtained by reacting 3-amino-1,2,5-oxadiazoles with phosgene in diluent, for example toluene and/or pyridine, at -20 to 50°C. Substd. furazane of formula III, useful for insecticides, miticides, can be prepared by reacting the compds. of formula I, preferably in the presence of a catalyst and a diluent, with the amine of the formula, NH 2 R 1 (R 1 is phenyl which may be substd.). COPYRIGHT: (C)1994,JPO