STUDIES ON THE GENERATION OF DIHALOCARBEN E AND THE REACTION-MECHANISM OF MIXED POLYHALOMETHANE WITH MAGNESIUM

The reaction of CHBr3/CHCl3 or CHBr3/CCl4 with magnesium under general Grignard reaction condition is studied and is for the first time foun d to produce dihalocarbene which is trapped with some different olefin s to prepare the gem-dihalocyclopropane derivatives in good yields. Th e reaction having advantages of easy work-up, mild reaction condition and high yield is a novel convenient method for the generation of diha locarbene. A possible mechanism (Single Electron Transfer, SET) is des cribed. The effect of different reaction condition on the reaction is studied.