Migratory insertion reaction of a phosphenium ligand into Mo- and W-alkyl bonds

Article abstract of DOI:10.1016/S0022-328X(96)06615-6

Treatment of Cp(CO)₂MeM{PN(Me)CH₂CH₂X(OR)} (M = Mo, W; X = NMe, O) with BF₃ · OEt₂ and then with PPh₃ yields trans-[Cp(CO)₂(PPh₃)M{PN(Me)CH₂CH₂X(Me)}]BF₄. Reaction of Cp(CO)₂MeM{P(OMe)₃} (M = Mo, W) with BF₃ · OEt₂ and then with PPh₃ gives a mixture of [Cp(CO)₂(PPh₃)M{P(OMe)₂Me}]BF₄ and [Cp(CO)₂(PPh₃)M{P(OMe)₃}]BF₄. These reactions reveal that migratory insertion of a phosphenium ligand into an M-alkyl bond (M = Mo, W) takes place. The structures of trans-[Cp(CO)₂(PPh₃)Mo{PN(Me)CH₂CH₂NMe(Me)}]OTf and [Cp(CO)₂(PPh₃)W{P(OMe)₃}]BF₄ were determined by single crystal X-ray diffraction studies.