Metal-Centered Ferrocene Clusters from 5-Ferrocenylpyrimidine and Ferrocenylpyrazine

A series of metal-centered ferrocene compounds has been designed by using 5-ferrocenylpyrimidine (L1) and ferrocenylpyrazine (L2). These ligands, when combined with transition metal salts, produce mixed-metal polynuclear complexes with structural diversity. Reaction of L1 with M (SCN)2 (M = Ni, Co) produces the pinwheel-like 4:1 complexes (L1)4·M(SCN)2, while reactions of L1 and L2 with Cu(NO3)2 give the 3:1 complex (L1)3·Cu (NO3)2 and the 2:1 complex (L2)2·Cu(NO3)2, respectively. Reactions of L1 and L2 with M(hfac)2 (hfac = 1,1,1,5,5,5-hexafluoroacetylacetonate, M = Mn, Ni, Cu, Zn) produce 2:1 complexes (L)2·M(hfac)2 with cis and trans configurations, respectively. Crystal structures as well as solid-state electrochemical properties of these redox active complexes were investigated.