Synthesis and Structure of Bis(pi-cyclopentadienyl)vanadium(IV) 1,10-Phenanthroline and 2,2'-Bipyridine Compounds and Their Interactions with Artificial Membranes.

The reaction of in situ generated Cp2V(OTf)2 (Cp = cyclopentadienyl; OTf = O3SCF3) with excess 1,10-phenanthroline and 2,2‘-bipyridine yields the d1 vanadocene coordination compounds [Cp2V(phen)][OTf]2 (1) and [Cp2V(bpy)][OTf]2 (2), respectively. The compounds have been characterized by UV−vis and EPR spectroscopy and by cyclic voltammetry. The complexes have relatively low vanadium(IV)−vanadium(III) reduction potentials (−0.62 V vs Cp2Fe+/0 in acetonitrile). Structures of 1 and 2 have been determined by X-ray crystallography. Compound 1 crystallized in a monoclinic system, space group P21/n, with a = 10.2763(5) A, b = 18.1646(9) A, c = 13.5741(7) A, β = 99.4150(10)°, and Z = 4. Refinement of its structure by full-matrix least-squares techniques gave final residuals R = 0.040 and Rw = 0.096. Compound 2 crystallized in a monoclinic system, space group P21/c, with a = 10.6451(6) A, b = 18.3863(10) A, c = 12.6993(7) A, β = 98.6220(10)°, and Z = 4. Refinement of its structure by full-matrix least-squares tech...