181034-22-0Relevant academic research and scientific papers
Chemistry of a new family of carboxyl-chelated ruthenium and osmium aryls incorporating the imine - Phenol motif
Ghosh, Prasanta,Pramanik, Amitava,Chakravorty, Animesh
, p. 4147 - 4152 (2008/10/08)
The reaction of carbonylhalo[4-methyl-6-(NR-iminiomethyl)phenolato-C 2,O]bis(triphenyl-phosphine)metal(II), MII(η2-RL)(PPh3)2(CO)X (M = Ru, Os; X = Cl, Br; R = Ph, p-MeC6H4), 1, with sodium carboxylates has afforded carbonyl(carboxylato)[4-methyl-6-(NR-iminomethyl)phenol-C 2]bis(triphenylphosphine)metal(II), MII(η1-RL)(PPh3)2(CO)(η 2-R′CO2) (R′ = Me, Ph), 2. The reaction is believed to proceed via initial associative cis attack on halide by carboxylate. The reaction 2 → 1 occurs upon treatment of 2 with excess halide. Spectral (UV-vis, IR, 1H NMR) and electrochemical (metal redox) data for 2 are reported. Structure determination of Ru(η1-MeC6H4L)(PPh3) 2(CO)(η2-MeCO2) and Ru(η1-MeC6H4L)(PPh3) 2(CO)-(η2-PhCOa)·C6H6 has revealed trans (PPh3)2 geometry, the MeC6H4L ligand being bonded via an aromatic carbon atom lying cis to the CO molecule. In the H-bonded phenol-imine function the bond parameters for the acetate complex are as follows: O1-H, 1.14(3) A?; N?H, 1.52(3) A?; O1?N, 2.592(10) A? O1-H?N, 156(1)°. In the 1 → 2 interconversion, iminium-phenolate to imine-phenol tautomerization and a sterically controlled change in rotational conformation are involved.
