Transition metal complexes with amidinato ligands: The ubiquitous tris-chelated structural motif

The syntheses, crystal and molecular structures of eight transition metal compounds possessing ligands of the type [(p-tol)-NC(H)N(p-tol)](-) (DTolF), [(phenyl)NC(H)N(phenyl)](-) (DPhF), and the corresponding triazenato ligands [(phenyl)NNN(phenyl)](-) (DPhTA) are presented. Common to all of the compounds is a homoleptic tris-chelated structure with virtual Dg symmetry. Crystallographic data for the compounds are as follows: Cr(DPhF)(3) . tol (1), monoclinic, C2/c with a = 21.015(3) Angstrom, b = 15.925(2) Angstrom, c = 12.896(1) Angstrom, beta = 116.628(8)degrees and Z = 4; Cr(DTolF)(3) (2) and Fe(DTolF)(3) (4), monoclinic, C2/c with a = 12.654(2), 12.725(4) Angstrom, b = 33.393(2), 33.440(7) Angstrom, c = 9.273(2), 9.281(1) Angstrom, beta = 94.17(2), 93.80(2)degrees and Z = 4, respectively; Fe(DPhF)(3) (3), orthorhombic, Peen with a = 10.902(2) Angstrom, b = 18.539(3) Angstrom, c = 16.412(3) Angstrom, and Z = 4; Ru(DTolF)(3) . 0.57C(6)H(14) (5) and Co(DTolF)(3) . 0.56C(6)H(14) (6), trigonal, Ri with a = 14.353(4), 14.100(2) Angstrom, c = 35.51(2), 36.340(8) Angstrom and Z = 6, respectively; Fe(DPhTA)(3) . tol (7), monoclinic, 12/a with a = 13.265(4) Angstrom, b = 16.182(2) Angstrom, c = 17.855(5) Angstrom, beta = 99.53(1)degrees and Z = 4; [Li(THF)(4)][Fe(DPhTA)(3)] (8), orthorhombic, Pbcn with a = 13.527(1) Angstrom, b = 17.827(2) Angstrom, c = 20.702(2) Angstrom and Z = 4.