Formation of a Six-Membered Metallacycle Consisting of Iron, Carbon, Phosphorus, Boron, and Two Oxygens: The First Example of Precedence of Migratory Insertion of CO into an M−C Bond over OR Abstraction from Coordinating Phosphite by BF3

Treatment of Cp(CO)MeFe{P(OMe) 3 } with BF 3 ·OEt 2 and then PPh 3 gave a six-membered metallacyclic complex, Cp(PPh 3 )FeC(Me)OBF 2 OP(OMe) 2, which is suggested by its NMR data and X-ray analysis to be best described as a carbene phosphite metallacycle.