Synthesis and crystal structure of N-heterocyclic carbene complex of silver

New imidazolium salt, [m-C6H4(CH2ImMe)2]Cl2 (1) was prepared by quaterization of N-methylimidazole with m-xylylene dichloride. A novel monocarbene silver dinulear complex, [m-C6H4(CH2ImMeAgCl)2] (3) was obtained by reacting 1 and Ag2O in CH2Cl2. The structure of 3 was determined by X-ray crystallography. The geometry around the Ag atoms in 3 is linear, and each Ag atom is bi-coordinated by a carbon and chloride ion.