Structures, preparation and catalytic activity of ruthenium cyclopentadienyl complexes based on pyridyl-phosphine ligand

Abstract

Ruthenium complexes [( η 5-C 5H 5)Ru( κ 1- P-PPh 2Py)(PPh 3)Cl] ( 1) and [( η 5-C 5H 5)Ru( κ 2- P- N-PPh 2Py)(PPh 3)] + ( 1a) containing diphenyl-2-pyridylphosphine (PPh 2Py) are reported. Coordinated PPh 2Py in the complex [( η 5-C 5H 5)Ru( κ 1- P-PPh 2Py)(PPh 3)Cl] ( 1) exhibits monodentate behavior. In presence of NH 4PF 6 in methanol at room temperature it afforded chelated complex [( η 5-C 5H 5)Ru( κ 2- P, N-PPh 2Py)(PPh 3)] + ( 1a). Further, 1 reacted with various species viz., CH 3CN, NaCN, NH 4SCN and NaN 3 to afford cationic and neutral complexes [( η 5-C 5H 5)Ru( κ 1- P-PPh 2Py)(PPh 3)L] + and [( η 5-C 5H 5)Ru( κ 1- P-PPh 2Py)(PPh 3)L] [L = CH 3CN ( 1b); CN − ( 1c); N 3 − ( 1d) and SCN − ( 1e)] and it’s reaction with N, N-donor chelating ligands dimethylglyoxime (H 2dmg) and 1,2-phenylenediamine (pda) gave cationic complexes [( η 5-C 5H 5)Ru( κ 1- P-PPh 2Py)( κ 2- N- N)]PF 6 [ κ 2- N- N = dmg ( 1f) and pda ( 1g)] . The complexes 1–1g have been characterized by physicochemical techniques and crystal structures of 1, 1a, 1c, 1e and 1f have been determined by single crystal X-ray analyses. Catalytic potential of the complex 1 has been evaluated in water under aerobic conditions. It was observed that the complex 1 selectively catalyzes reduction of aldehyde into alcohol.