Modulating the reduction potential of mononuclear cobalt(II) complexes via selective deprotonation of tris[(2-benzimidazolyl)methyl]amine

Remote site deprotonation of the coordinated tripodal ligand, tris((2-benzimidazolyl)methyl)amine, was examined using electronic spectroscopy and electrochemistry techniques. The solid-state structures CoH(3)1(tba)(NCS)]+ and CoH(2)1(tba)(NCS)] are reported. These complexes crystallized in the triclinic space group P1 a = 13.3043(2) A, b = 13.8019(2) A, c = 14.1322(2) A, alpha = 63.6670(10) degrees, beta = 68.0590(10) degrees, gamma = 81.8960 degrees; Z = 2] and the monoclinic space group P2(1)/n a = 15.3530(9) A, b = 11.0645(6) A, c = 19.1319(10) A, beta = 105.6750(10) degrees; Z = 4], respectively. Preliminary results suggest that selective and reversible deprotonation of coordinated benzimidazolyl ligands can tune the reduction potential of several isostructural cobalt(II) complexes.