3- and 4-Pyridinecarboxylic acidN-oxide complexes with manganese(II), cobalt(II) and nickel(II) chlorides |
| |
Authors: | Larry S Gelfand Louis L Pytlewski Chester M Mikulski Anthony N Speca Nicholas M Karayannis |
| |
Institution: | (1) Department of Chemistry, Drexel University, 19104 Philadelphia, Pa, USA;(2) Department of Chemistry and Physics, Beaver College, 19038 Glenside, Pa, USA;(3) Research Division, USI Chemicals Co., 45237 Cincinnati, Ohio, USA;(4) Amoco Chemicals Corporation, 60540 Naperville, Il, USA |
| |
Abstract: | Summary During interaction of ethanol-triethyl orthoformate solutions of nicotinic or isonicotinic acidN-oxides (LH and LH, respectively) with MCl2 (M = Mn, Co, Ni), only one true adduct, of the Ni(LH)3Cl2 · 2 H2O type was obtained. In all other cases, partial substitution of Cl– ions with the corresponding pyridinecarboxylateN-oxide anionic ligands (L or L) occurred. As a result, mixed ligands (LH-L or LH-L) were precipitated, as follows: Mn(LH)2LCl, Co(LH)LCl, Mn(LH)LCl · 4H2O, Co(LH)LCl · H2O and Ni2(LH)LCl3 · 6 H2O. The insolubility of the new complexes in all common solvents, combined with the pronounced tendency of the 3- and 4-pyridinecarboxylates and theirN-oxides to function as bidentate bridging ligands, favours bi- or polynuclear structures. Spectral data suggest that Ni(LH)3Cl2 · 2 H2O is hexacoordinate, and the rest of the new complexes pentacoordinate. Bi- or polynuclear structures, involving double -M-(L)2-M- or-M-(LH)2-M- and single -M-(L)-M- or-M(L)-M-(LH)-M- bridges, were proposed on the basis of the overall evidence; additional features of the proposed structural types are: exclusively coordinated chloro ligands, in all cases; aqua ligands Co(LH)LCl · H2O]; lattice water Ni(LH)2Cl2 · 2H2O]; both lattice and coordinated H2O Mn(LH)LCl · 4H2O, and Ni2(LH)LCl3 · 6H2O]; and, with the exception of Ni2(LH)LCl3 · 6 H2O, terminal, unidentate, N-O oxygen-bonded LH or LH ligands.Abstracted in part from the Ph.D. Thesis (in preparation) of L. S. Gelfand, Drexel University. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|