摘要:
Ruthenium(II) carbonyl complexes containing triarylphosphines and hybrid ligands PPh2-X (X = o-dimethylaniline - P-N, o-pyridine - P-Py, or o-anisole - P-O) were synthesized and characterized. Six new complexes with the formula cis,trans-[RuCl2(CO)(PPh2-X)(PR3)] (X = o-dimethylaniline. R = Ph 1a; X = o-pyridine, R = Ph 2a; X = o-anisole, R = Ph 3a; X = o-dimethylaniline, R = p-tol 1b; X = o-pyridine, R = p-tol 2b; and X = o-anisole, R = p-tol 3b) were obtained by starting from the appropriate precursors, [RuCl2(CO)(DMF)(PPh3)(2)] or [RuCl3(CO)(DMF)(P{p-tol}(3))(2)]. The two chlorine atoms are in cis position to each other, and the monophosphine (PPh3 or P{p-tol}(3)) is in trans position to the nitrogen or oxygen of the PPh2-X ligand. The synthesized complexes were characterized by 1D-H-1, P-31{H-1} and 2D-correlations HMBC P-31-H-1 NMR, vibrational spectroscopy, elemental analysis, and X-ray diffraction structural determination (for complexes 1a, 2a center dot CH2Cl2, 3a, and 3b center dot CH2Cl2). Only the complexes containing the P-O ligand (3a and 3b) reacted with carbon monoxide (at 1 atm and room temperature). The NMR (P-31{H-1}, H-1) data was compatible with carbon monoxide coordination at the OCH3 position, which led to the formation of dicarbonyl complexes [RuCl2(CO)(2)(P-O)(PRA(3))] (R = Ph 4a or p-tol 4b), and proved the hemilabile behavior of the P-O ligand. In addition, the complexes underwent isomerization in solution when exposed to ambient light, and the products were analyzed by P-31{H-1} NMR. The X-ray structures and the chemical shift in the P-31 NMR spectra were correlated and discussed. (c) 2012 Elsevier Ltd. All rights reserved.