Reactions of the cationic but-2-yne complex [WI(CO)(NCMe){Ph2P(CH2)PPh2} (η2-MeC2Me)][BF4] with bidentate nitrogen donor ligands

Abstract Reaction of the complex [WI(CO)(NCMe){Ph 2 P(CH 2 )PPh 2 }(η 2 MeC 2 Me)][BF 4 ] with an equimolar quantity of NN {NN = 2,2′-bipyridyl, 1,10-phenanthroline, 5,6-dimethyl-1,10-phenanthroline, N , N′ -cyclohexyldiazabutadiene, N , N′ - t butyldiazabutadiene or N , N′ - p -methoxyphenyldiazabutadiene} at room temperature in CH 2 Cl 2 smoothly affords good yields of the new dicationic mixed ligand complexes [W(CO)(NN){Ph 2 P(CH 2 )PPh 2 }(η 2 MeC 2 Me)][BF 4 ]I ( 1 – 6 ). The dicationic nature of these complexes was confirmed by reaction of [W(CO)(2,2′-bipy){Ph 2 P(CH 2 )PPh 2 }(η 2 MeC 2 Me)][BF 4 ]I with two equivalents of Na[BPh 4 ] in acetonitrile to give the bistetraphenylborate) complex [W(CO)(2,2′-bipy){Ph 2 P(CH 2 )PPh 2 }(η 2 MeC 2 Me)][BPH 4 ] 2 ( 7 ). 13 C NMR spectroscopy indicates that the but-2-yne acts as a four-electron donor in these complexes.