Inorganic Chemistry, Vol.33, No.13, 2711-2712, 1994
Unusually Stable Radical Anionic Complexes ((Co)5Mnre(Co)3(Bpm))Center-Dot-, ((Co)5Mnre(Co)3(Bpm)Re(Co)3Br)Center-Dot-, (Os3(Co)10(Bpm))Center-Dot-, and (Os3(Co)10(Bpm)Re(Co)3Br)Center-Dot- (Bpm = 2,2’-Bipyrimidine) Studied with Cyclic Voltammetry and Ir Spectroelectrochemistry at Variable Temperatures
One-electron reduction of the metal-metal-bonded complexes [(CO)5MnRe(CO)3-(BPM)], [(CO)5MnRe(CO)3(BPM)Re(CO)3Br], [Os3(CO)10(BPM)], and [Os3(CO)10(BPM)Re(CO)3Br] is reported. (Spectro)electrochemical experiments at variable temperatures afforded evidence on the stabilizing role of the BPM ligand, which is able to accommodate the unpaired electron in its lowest pi* orbital. Whereas [Os3(CO)10(BPM)].- and [(CO)5MnRe(CO)3-(BPM].- undergo a splitting of the metal-metal bond, retention of structure upon reduction has been observed for the complexes with the bridging BPM ligand.