Synthesis, structure and bonding of new mono- and dinuclear molybdenum complexes containing pyridine-2-thiolate (pyS) and different P-donors

Abstract

Three new molybdenum complexes have been synthesized from one-pot reactions between Mo(CO)3(NCMe)3 and pyridine-2-thiol (pySH) in the presence of different P-donors. Reaction with P(OMe)3 in MeCN at ca. 55°C gives Mo(CO)2[P(OMe)3](κ2-pyS)2 (1) and Mo(CO)4[P(OMe)3]2 (2). A similar reaction involving bis(diphenylphosphino)methane (dppm) furnishes the dinuclear species Mo2(CO)4(μ,κ2-pyS)2(κ2-dppm) (3) together with the mononuclear complexes Mo(CO)(κ2-pyS)2(κ2-dppm) (4) and Mo(CO)4(κ2-dppm) (5). With bis(diphenylphosphino)ethane (dppe) only the mononuclear complexes Mo(CO)(κ2-pyS)2(κ2-dppe) (6), Mo(CO)4(κ2-dppe) (7), and Mo(CO)3(κ1-dppe)(κ2-dppe) (8) resulted. Complexes 1, 3, and 6 have been characterized by single-crystal X-ray diffraction analyses and the bonding in 1 and 3 has been evaluated by density functional theory (DFT) calculations, optimized structures being discussed relative to the observed solid-state structures.