Perchlorinated isocyanide dichlorides prepn - from n-chloro -isocyanide dichloride and chloro cpds

摘要

Process for preparing perchlorinated isocyanide dichlorides (I), which N-chloro-isocyanide dichloride (II) is reacted with a cpd. of formula (III): (where R1 is H or Cl; R2 (same or different) are Cl or -N= CCl2) in the presence of at least the stoichiometric amt. of Lewis acid at -20 to +70 degrees C. - (I) are plant-protection agents or intermediates thereof, and are also intermediates for isocyanates. - The reaction temp. is pref. 40-70 degrees C, esp. 55-60 degrees C. The Lewis acid is pref. AlCl3 and/or AlBr3, and is pref. used in an excess of =100%, pref. 5-20%. (III) may be CCl4, CHCl3, Cl3C-N=CCl2 or Cl2C(N=CCl2)2. - The process is of particular interest for the prodn. of (IV), but may also be used to prepare (V); (VI) is a by-product. If (V) is required as the main product, it is prefd. to start from (II) and (IV). A solvent, e.g. CH2Cl2, chlorobenzene or dichlorobenzene may be used.