Syntheses and crystal structures of di-, tri- and tetra-nuclear cobalt(II)-lanthanide(III) carboxylate complexes

Reaction of Co( NO3)(2). 6H(2)O, Ln(NO3)(3). 6H(2)O, pivalic acid and quino line in different stoichiometric molar ratios in EtOK produced three struct ural types of carboxylate-bridged cobalt ( II)-lanthanide ( III) compounds, [CoDy (O2CCMe3)(5) (C9H7N) (H2O )]. 0.5C9H7N 1, [Co2Ce(O2CCMe3)(6) (C9H7N) (2) (NO3) ] 2 and [ Co2Y2 (O2CCMe3)(8) ( C9H7N )(2) (NO3)(2)] 3. Complex 1 crystailizes in triclinic space group P (1) over bar, with a = 12. 2457(5), b = 13.3210(5), c = 15.0938(6) Angstrom, alpha = 111.574(1), beta = 93.486 (1), gamma = 102.398(4)degrees, V = 2209.60(15) Angstrom (3) and Z = 2. Com plex 2 crystallizes in triclinic space group P (1) over bar, with a = 11.89 5 (3), b = 12.6941(4), c = 22.1633(7) Angstrom, alpha = 98.52(1), beta = 98 .01(2), gamma = 117.07(2)degrees, V = 2864. 7(7) Angstrom (3) and Z = 2. Fi nally, complex 3 crystallizes in triclinic space group P (1) over bar, with a = 10.9307(6), b = 12.4501(6), c = 13. 7881(7) Angstrom, alpha = 85.772(1 ), beta = 84.510(2), gamma = 73.180(1)degrees, V = 1787.4(2) Angstrom (3) a nd Z = 1. In the three above cases, the neighboring cobalt(II) and lanthani de(III) ions are bridged by three pivalate ligands in the syn-syn modes wit h the intermetallic distances of 3.977(1), 4.097(1) and 3.922(8) Angstrom f or 1-3, respectively.