SEVEN-COORDINATE PYRIDINE-2-THIONE AND PYRIMIDINE-2-THIONE COMPLEXES OF MOLYBDENUM (II) TUNGSTEN (II)

Equimolar quantities of [WI(2) (CO)(3)(NCMe)(2)] and pyridine-2-thione (pySH) or pyrimidine-2-thione (pymSH) react in CH(2)Cl(2) at room temperature to give the dimeric complexes [{W(mu-I)I(CO)(3) (pySH)}(2)] (1) or [{W(mu-I)I(CO)(3)(pymSH)}(2)]center dot 1/2 CH(2)Cl(2) (2), respectively. Reaction of [MI(2)(CO)(3)(NCMe)(2)] (M = Mo or W) with two equivalents of pySH (for M = Mo only) or pymSH in CH(2)Cl(2) afforded the bis(ligand) complexes [MoI(2)(CO)(3)(pySH)(2)] (3), [MoI(2)(CO)(3)(pymSH)(2)] (4) or [WI(2)(CO)(3)(pymSH)(2)]center dot CH(2)Cl(2) (5) respectively. Reaction of [WI(2)(CO)(3)(NCMe)(2)] with two equivalents of PPh(3) or one equivalent of Ph(2)P(CH(2))(n)PPh(2) (n = 1 to 6) in CH(2)Cl(2) at room temperature, followed by an in situ reaction with one equivalent of pySH yielded the cationic complexes [WI(CO)(3)(PPh(3))(2)(pySH)]I (6) or [WI(CO)(3){Ph(2)P(CH(2))(n)PPh(2)}(pySH)]I (7 -> 12), respectively.