BIS(HOMOLEPTIC) VS HETEROLEPTIC COPPER(I) COMPLEXES - ELECTROSYNTHESIS, SPECTROSCOPY, AND CRYSTAL-STRUCTURE OF -4(SR)(6)](2-))CENTER-DOT-3(CH3CN)CENTER-DOT(RSH), BIK-EQUALS-BIS(2-METHYL-IMIDAZOL-2-YL)KETONE, R-EQUALS-O-TOLYL())(2)([CU)

Anodic oxidation of copper in acetonitrile/2 mM tetrabutylammonium per chlorate and in the presence of bis (N-methylimidazol-2-yl) ketone (BI K) and excess o-thiocresol RSH yields the title compound as main produ ct. Whereas the dianionic cluster [Cu-4(SR)(6)](2-) is similar to prev iously reported such species with R = phenyl or methyl, the purple cat ions [Cu(BIK)(2)](+) exhibit spectroscopic and structural effects of p i back bonding between electron-rich Cu-1 and the pi acceptor ligand B IK. In contrast to the formally related [Zn(BIK)(2)](2+), the copper(I ) complex cations exhibit distorted tetrahedral structures with almost coplanar BIK chelate arrangements which ensures maximum metal-ligand pi interaction.