Sequential Electrophilic Substitution Reactions of Tungsten-Coordinated Phosphenium Ions and Phosphine Triflates

摘要

Abstraction of chloride from [W(CO)_(5){PPhCl_(2)}] with AgOSO_(2)CF_(3) leads to the phosphine triflate complex [W(CO)_(5){PPhCl(OSO_(2)CF_(3))}] which undergoes electrophilic substitution reactions with N ,N -diethylaniline, anisole, N ,N -dimethyl-p -toluidine, toluene, biphenyl, naphthalene, 2,7,9,9-tetramethyl xanthene, and allyltrimethylsilane to form the chlorophosphine complexes [W(CO)_(5){PPhClR}], where R = p -diethylanilinyl, p -anisyl, 2-(N ,N -dimethyl-4-methylphenyl), p -tolyl, p -phenylphenyl, 1-naphthyl, 4-(2,7,9,9-tetramethylxanthyl), and allyl. Abstraction of the second chloride with AgOSO_(2)CF_(3) leads, in most cases, to the respective phosphine triflates [W(CO)_(5){PPhR(OSO_(2)CF_(3))}], which react with ferrocene to form the ferrocenyl phosphine complexes [W(CO)_(5){PPhR(C_(10)H_(9)Fe)}]. The W(CO)_(5) unit can be removed via photolysis in the presence of bis(diphenylphosphino)ethane to form metal-free phosphines.