REACTIVITY OF COORDINATIVELY UNSATURATED TRIVALENT CHROMIUM COMPLEXESWITH SULFUR - PREPARATION OF NOVEL SULFIDE-BRIDGED DINUCLEAR CR-IV DERIVATIVES

The homoleptic Cr-III amide complexes [(RR'N)(3)Cr] [R = R' = cyclohex yl (1a); R = adamantyl. R' = 3,5-Me2Ph (1b)] were prepared and charact erized. Reactions with elemental sulfur produced the corresponding din uclear complexes [{(RR'N)(2)Cr}(2)(mu-S)(2)] (2) through loss of one a mide group, These two new dinuclear Cr-IV species are paramagnetic wit h magnetic moments lower than expected for the d(2) electronic configu ration of Cr-IV. Magnetic measurements and ab initio calculations were carried out to elucidate the nature of magnetic interactions in these dinuclear systems, The molecular structures of 1a and 2a were elucida ted by X-ray crystal structures.