Synthesis and X-ray structural characterization of mono(aminophosphine) derivatives of molybdenum hexacarbonyl, Mo(CO)5L {L = P(NC5H10)3, P(Ph)(NC4H8O)2 or P(Ph){N(i-C3H7)2}(NC4H8O)}

Equimolar reactions of molybdenum hexacarbonyl with tris(piperidino)phosphine (L1), bis(morpholino)(phenyl)phosphine (L2), and (Di-isopropylamino)(morpholino)(phenyl) phosphine (L3), which are examples of symmetrically and unsymmetrically substituted tertiary(amino)phosphines, afford the corresponding mono derivatives, Mo[P(NC5H10)3)](CO)5 (1), Mo[P(Ph)(NC4H8O)2](CO)5 (2), and Mo[P(Ph){N(i-C3H7)2}(NC4H8O)](CO)5 (3) in moderate yields as air stable crystalline solids. In the case of L1, some amount of trans-bis derivative, Mo[P(NC5H10)3)]2(CO)4 (4), was also isolated. X-ray structures of 1, 2, and 3 have been determined. Compounds 1 and 2 crystallize in the monoclinic system with space group P21/c, while 3 crystallizes in the triclinic system with space group Pī. While the Mo-P and Mo-Cax bond distances in these complexes are comparable with those of other P-C bonded phosphines, the presence of chiral phosphine seems to induce a relatively weaker interaction with the molybdenum center. Intermolecular hydrogen bonding is seen in compound 1.