MONONUCLEAR AND DINUCLEAR PHOSPHINE COORDINATED 1,4-BIS(DIPHENYLPHOSPHINO)ETHYNE 7-COORDINATE COMPLEXES OF MOLYBDENUM(II) AND TUNGSTEN(II)

Equimolar quantities of the seven-coordinate compounds [MI2(CO)3(NCMe)2] (M = Mo and W) and Ph2PCCPPh2 react in CH2Cl2 at room temperature to afford the Ph2PCCPPh2 phosphine coordinated bridged complexes [M2I4(CO)6(μ-Ph2PCCPPh2)2] in good yield. Reaction of [MI2(CO)3(NCMe)2] with two equivalents of Ph2PCCPPh2 in CH2Cl2 at room temperature gives the mononuclear compounds [MI2(CO)3(Ph2PCCPPh2)2]. 31P NMR studies show the Ph2PCCPPh2 ligand in [MI2(CO)3(Ph2PCCPPh2)2] to have monodentate phosphine coordination. © 1990.