Département de chimie moléculaire

The authors have isolated and characterized (x-ray crystallog., EXAFS, EPR, absorption spectra) the first dicopper system with a {\{}Cu2S2{\}} core that is stable in the two oxidn. states (1,1) and (1.5,1.5) and that can be related to the biol. CuA site. However, in contrast to CuA, the short Cu-Cu distance of the reduced complex [Cu2(L')] [1, L' = mono-methylene-linked 2,2'-(2,2'-bipyridine-6,6'-diyl)bis(1,1-diphenylethanethiolate)] notably increases in the oxidized mixed valence form [Cu2(L')](B(C6F5)4) (2), despite the geometric constraints imposed by L'. [on SciFinder(R)]