Regioselective silylphosphination of methyl vinyl ketone with complexes containing cyclic and linear iron– silicon–phosphorus reacting sites

Treatment of Cp*(CO)Fe{(kappa)^2(Si,P)-SiMe2PPh2} with methyl vinyl ketone gave a 1,2-addition product, Cp*(CO)Fe{(kappa)^2(Si,P)-SiMe2OCMe(CH=CH2)PPh2}. A linear-type Cp*(CO)2FeSiMe2PPh2 also reacted with the ketone to yield a 1,4-addition product, Cp*(CO)2Fe{(kappa)^1(Si)-SiMe2OC(Me)=CHCH2PPh2}, which was further converted to a seven-membered metallacycle, Cp*(CO)Fe{(kappa)^2(Si,P)-SiMe2OC(Me)=CHCH2PPh2}, upon photolysis.