VERFAHREN ZUR HERSTELLUNG VON (BETA)-HALOGEN-TERT.-ALKYLISOCYANATEN

摘要

The invention relates to a process for the preparation of known beta -halogeno-tert.-alkyl isocyanates of the formula (I) in which X represents chlorine, Y represents hydrogen or chlorine, R1 represents in each case straight-chain or branched alkyl or halogenoalkyl and R2 represents in each case straight-chain or branched alkyl, halogenoalkyl or optionally halogen- and/or trifluoromethyl-substituted phenyl, where tert.-alkyl isocyanates of the formula (II) (II) in which R1 and R2 have the meaning given above, are converted to the corresponding tert.-alkylcarbamoyl chlorides by means of hydrogen chloride gas, these are reacted with elemental chlorine under irradiation or in the presence of catalysts, and finally the beta -halogeno-tert.-alkyl isocyanates are liberated by dehydrohalogenation at elevated temperature.