Stabile Carben-Addukte des Chlors / Stable Carbene Adducts of Chlorine

Abstract The carbene adducts 3a-c (R1 = Me, Et, iso-Pr; R2 = Me) are formed from the 2,3-dihydro-imidazol-2-ylidenes 1a-c and 1,2-dichloroethane as air-sensitive solids in good yields. The compounds exhibit a reactive Cl-Cl bond. Benzene is chlorinated by 3a,b to give chlorobenzene and the imidazolium salts 10a,b under mild conditions. 3c acts as a chloride donor to give with AICI3 and SO2 the 2-chloroimidazolium salts 12c and 13c (X = AlCl4, SO2Cl). On hydrolysis, the less reactive hydrate salt 14c is formed from 3c. The X-ray structures of 10a and 14c are reported.