W(O) (η3-PPh2(o-C6H4)C5Ph4H) (η2-C2Ph2): A complex containing oxo and metallacyclohexadiene ligands from Cdouble bond; length as m-dashO bond activation and alkyne coupling reactions of W(NCMe) (η2-C2Ph2)3 with PPh2(o-C6H4)C(double bond; length as m-dashO

Reaction of W(NCMe) (η2-C2Ph2)3 (1) and PPh2(o-C6H4)C(double bond; length as m-dashO)H in refluxing toluene affords W(O) (η3-PPh2(o-C6H4)C5Ph4H) (η2-C2Ph2) (2). The structure of 2 reveals that an oxygen atom and a pentadienyl group are attached to the tungsten center, apparently arising from activation of the formyl Cdouble bond; length as m-dashO bond and coupling of the diphenylacetylene ligands.