THE REDUCTION AND OXIDATION OF CATIONIC CARBONYL-COMPLEXES OF MANGANESE WITH PHOSPHONIODITHIOFORMATE - X-RAY CRYSTAL-STRUCTURE OF [MN(CO)(4)(S(2)CPCY(3))]CLO4

Manganese carbonyl complexes of the types [Mn(CO)(4)(S(2)CPCy(3))]ClO4 (1), fac-[Mn(CO)(3)L(S(2)CPCy(3))]ClO4(L=P(OMe)(3) (2a), PCy(3) (2b), or PEt(3) (2c)), and cis,trans-[Mn(CO)(2)L(2)(S(2)CPR(3))]ClO4(R=Cy, L=P(OMe)(3) (3a), R=Cy, L=PEt(3) (3b), R=Et, L=PEt(3) (3c)) have been prepared, and the crystal structure of compound (1) has been determine d by X-ray diffraction. Their redox behaviour have been studied by cyc lic voltammetry and controlled potential electrolysis, showing that th ey undergo one-electron reduction and one-electron oxidation at potent ials that depend mainly on the number of carbonyls. The results have b een explained on the basis on an MO study at an EH level carried out o n the model complexes [Mn(CO)(4)(S2CPH3)](+) (1b), fac-[Mn(CO)(3)PH3(S 2CPH3)](+) (26), cis,trans-[Mn(CO)(2)(PH3)(2)(S2CPH3)](+) (3d), mer-[M n(CO)(3)PH3(S2CPH3)](+) (4), trans,cis-[Mn(CO)(2)(PH3)(2)(S2CPH3)](+) (5), and cis, cis-[Mn(CO)(2)(PH3)(2)(S2CPH3)](+)(6).