Zur reaktion von metallkoordiniertem kohlenmonoxid mit yliden: XIV. Eisenacyl-phosphor-ylide mit elektronenreicher organometallgruppierung

Treatment of C₅Me₅(CO)₃Fe]BF₄ (I) with the phosphines Me₃P and Et₃P under thermal or photochemical conditions yields the novel iron salts C₅Me₅-(CO)₂(R₃P)Fe]BF₄ (R = Me (IIa), R = Et (IIb)) and C₅Me₅(CO)(Me₃P)₂Fe]BF₄ (IIc). The reaction of I and IIa with two mol of the ylide Me₃PCH₂ leads to the formation of the ironacyl-ylides C₅Me₅(CO)(L)FeC(O)CHPMe₃ (L = CO (IVa), Me₃P (IVb)). IVa selectively reacts at the “ylidic” carbon with the electrophilic reagents MeI, MeOSO₂F, Me₃SiOSO₂CF₃ to give the ironacyl-phosphonium salts C₅Me₅(CO)₂FeC(O)CH(R)PMe₃] X (VaVc), while IVb is partially converted to C₅Me₅(CO)₂FeC(O)CH₂PMe₃]BF₄ (IIIa) is obtained together with C₅Me₅-(CO)₂Fe]₂ from I and IVa.