Synthesis, X-ray structure, and physical and photophysical properties of the heterobimetallic complex Fe(eta(5)-C5H4PPh2)(2)Pt(bph)

A chromophore-electroactive compound, Fe(eta(5)-C5H4PPh2)(2)Pt(bph), where bph is the biphenyl dianion and Fe(eta(5)-C5H4Ph2)(2) is 1,1'-bis(diphenylp hosphino)ferrocene-P,P' has been synthesized. The single-crystal X-ray stru ctural characteristics of this heterobimetallic complex and its disolvated methylene chloride derivative are respectively as follows: empirical formul a C46H36FeP2Pt, triclinic, P (1) over bar, Z = 4, a = 9.777(2) Angstrom, b = 18.003(4) Angstrom, c = 20.882(4) Angstrom, alpha = 93.57(3)degrees, beta = 100.99(3)degrees, and gamma = 90.86(3)degrees, and empirical formula C48 H40Cl2FeP2Pt, monoclinic, P2(1)/n, Z = 4, a = 12.698(3) Angstrom, b = 14.16 1(3) Angstrom, c = 23.376(6) Angstrom, alpha = 90 degrees, beta = 94.107(14 )degrees, and gamma = 90 degrees. An electrochemical study shows that the a nodic potential for the oxidation of the ferrocenyl moiety of this compound increases by +0.13 V, compared to that for Fe(eta(5)-C5H4PPh2)(2). This ch ange in oxidation potential agrees well with the change in energy of 0.11 e V for the d pi(Fe) --> pi*(Cp) MLCT transition upon coordination with Pt. T he resultant excited state from the d pi(Pt) --> pi*(bph) MLCT transition i s readily quenched by the ferrocenyl moiety unit as expected, and charge-se parated redox-active centers are formed.