Copper and Bismuth Complexes Containing Dipyridyl gem-Diolato Ligands: Bi2[(2-Py)2CO(OH)]2(O2CCF3)4(THF)2 , Cu[(2-Py)2CO(OH)]2(HO2CCH3)2, and Cu4[(2-Py)2CO(OH)]2(O2CCH3)6(H2O)2, a Ferromagnetically Coupled Tetranuclear Copper(II) Chain

The reactions of the singly deprotonated di-2-pyridylmethanediol ligand (dpmdH-) with copper(II) and bismuth(III) have been investigated. A new dinuclear bismuth(III) complex Bi2(dpmdH)2(O2CCF3)4(THF)2, 1, has been obtained by the reaction of BiPh3 with di-2-pyridyl ketone in the presence of HO2CCF3 in tetrahydrofuran (THF). The reaction of Cu(OCH3)2 with di-2-pyridyl ketone, H2O, and acetic acid in a 1:2:2:2 ratio yielded a mononuclear complex Cu[(2-Py)2CO(OH)]2(HO2CCH3)2, 2, while the reaction of Cu(OAC)2(H2O) with di-2-pyridyl ketone and acetic acid in a 2:1:1 ratio yielded a tetranuclear complex Cu4[(2-Py)2CO(OH)]2(O2CCH3)6(H2O)2, 3. The structures of these complexes were determined by single-crystal X-ray diffraction analyses. Three different bonding modes of the dpmdHligand were observed in compounds 1-3. In 2, the dpmdHligand functions as a tridentate chelate to the copper center and forms a hydrogen bond between the OH group and the noncoordinating HO2CCH3 molecule. In 1 and 3, the dpmdHligand functions as a bridging ligand to two metal centers through the oxygen atom. The two pyridyl groups of the dpmdHligand are bound to one bismuth(III) center in 1, while in 3 they are bound two copper(II) centers, respectively. Compound 3 has an unusual one dimensional hydrogen bonded extended structure. The intramolecular magnetic interaction in 3 has been found to be dominated by ferromagnetism. Crystal data: 1, C38H34N4O14F12Bi2, triclinic P1h, a ) 11.764(3) Å, b ) 11.949(3) Å, c ) 9.737(1) Å, R )101.36(2)°, â ) 105.64(2)°, γ ) 63.79(2)°, Z ) 1; 2, C26H26N4O8Cu/CH2Cl2, monoclinic C2/c, a ) 25.51(3) Å, b ) 7.861(7) Å, c ) 16.24(2) Å, â ) 113.08(9)°, Z ) 4; 3, C34H40N4O18Cu4/CH2Cl2, triclinic P1h, a ) 10.494(2) Å, b ) 13.885(2) Å, c ) 7.900(4) Å, R )106.52(2)°, â ) 90.85(3)°, γ ) 94.12(1)°, Z ) 1.