Microwave methods for the synthesis of gold(III) complexes

New microwave methods were developed for the synthesis of cationic and neutral gold(III) complexes. Six examples of [AuCl2(N-N)][PF6], containing 2,2'-bipyridine-type ligands, and three examples of AuCl2(C-N), containing cyclometallated 2-phenylpyridine-type ligands, were successfully prepared. Two of the complexes, [AuCl2(5,5'-dimethyl-2,2'-bipyridine)][PF6] and [AuCl2(4,4',5,5'-tetramethyl-2,2'-bipyridine)][PF6], have not been previously reported. Generally, the microwave-heated reactions gave analytically pure products within minutes - a substantial improvement over conventional procedures. In conjunction, the thermal stabilities of some of the complexes were studied by thermogravimetric analysis. The transformation of AuCl3(2-(p-tolyl)pyridine) into its cyclometallated analog AuCl2(tpy), marked by the loss of a mass corresponding to HCl, was observed.