Reactions of Cp '(CO)(2)MnPPh2H with CH3COCl and CH3S(O)(2)Cl in THF/triethylamine: evidence of the first complex stabilization of a phosphorus homolog of the sulfonamides

The complex Cp'Mn(CO)(3) (Cp' = eta(5)-C5H4-CH3) reacts with P(C6H5)(2)H in THF to give Cp'(CO)(2)MnPPh2H (Ph = phenyl) (1), by substitution of one CO ligand. The reaction of 1 with CH3COCl and CH3S(O)(2)Cl in the presence of triethylamine occurs under electrophilic substitution on the diphenylphosp hane ligand yielding the acetyl and sulfonylphosphane complexes of manganes e(I) Cp'(CO)(2)MnPPh2COCH3 (2) and Cp'(CO)(2)MnPPh2S(O)(2)CH3 (3). The comp lex stabilization of these molecules, which are hitherto unknown in the fre e state, is only accomplished by blocking the free electron pair on phospho rus by coordination. The new complexes 1, 2 and 3 were analyzed by IR, H-1 and P-31 NMR spectroscopy and their similar structures are discussed. (C) 1 999 Elsevier Science S.A. All rights reserved.