7-COORDINATE TRIPHOS (TRIPHOS=PH(2)P(CH2)(2)PPH(CH2)(2)PPH(2) ) COMPLEXES OF MOLYBDENUM(II) AND MOLYBDENUM (II) AND TUNGSTEN(II) - [WI2(CO)(3)(ETA(2)-TRIPHOS)], A NOVEL MONODENTATE PHOSPHINE LIGAND

Equimolar quantities of [MI(2)(CO)(3)(NCMe)(2)] (M = Mo or W) and triphos {triphos = Ph(2)P(CH2)(2)PPh(CH2)(2)PPh(2)) react in CH2Cl2 at room temperature to give the dicarbonyl molybdenum complex [MoI2(CO),(eta(3)-triphos)] (1) or the tricarbonyl tungsten complex [WI2(CO)(3)(eta(2)-triphos)] (2). Refluxing (2) in CH2Cl2 for 15 min gave the eta(3)-triphos complex [WI2(CO)(2)(eta(3)-triphos)] (3). Preliminary studies of the reaction chemistry of(2) as a monodentate phosphine ligand are also described.