摘要:
Reaction of vanadium(III) chloride with 8-quinolinol (Hqn) gave a mononuclear vanadium(IV) complex, [VOCl2(H2O)(2)] 1) center dot 2H(2)qn center dot 2Cl center dot CH3CN, and three dinuclear vanadium(IV) complexes: [V2O2Cl2 (qn)(2)(H2O)(2)] (2) center dot Hqn, [V2O2Cl2(qn)(2)(C3H7OH)(2)] (3), and [V2O2Cl2(qn)(2)(C4H9OH)(2)] (4). Reaction of vanadium(III) chloride with 5-chloro-8-quinolinol (HClqn) gave four dinuclear vanadium(IV) complexes: [V2O2Cl2(Clqn)(2)(H2O)(2)] (5) center dot 2HClqn, [V2O2Cl2(Clqn)(2)(C3H7OH)(2)] (6), [V2O2Cl2(Clqn)(2)(C6H5CH2OH)(2)] (7), and [V2O2Cl2(Clqn)(2)(C4H9OH)(2)] (8) center dot 2C(4)H(9)OH. Reaction of vanadium(III) chloride with 5-fluoro-8-quinolinol (HFqn) gave two dinuclear vanadium(IV) complexes: [V2O2Cl2(Fqn)(2)(H2O)(2)] (9) center dot HFqn center dot 2H(2)O and V2O2Cl2(Fqn)(2)(C3H7OH)(2)] (10). X-ray structures of 1 center dot 2H(2)qn center dot 2Cl center dot CH3CN, 3, 4, 6, 7, 8 center dot 2 t-BuOH, and 10 have been determined. As to the mononuclear species 1 center dot 2H2qn center dot 2Cl center dot CH3CN, coordination of Hqn to vanadium does not occur, but protonation to Hqn occurs to give H(2)qn(+), which links 1's through hydrogen bonding, while each of the dinuclear species has a terminal and a bridging qn (or Clqn, Fqn) ligand, giving rise to a (V-O)(2) ring. Magnetic measurements of 3, 4, 6, 7, and 10 in solid form show very weak antiferromagnetic behavior, and the effective magnetic moments are close to spin only value (2.44) of d(1)-d(1) system, while ESR of 3 in THF shows dissociation to monomeric species. Change from mononuclear, 1, to dinuclear, 2, species was followed by the change of electronic spectrum. (C) 2009 Elsevier B. V. All rights reserved.