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

ABSTRACT: ion of chloride from [W(CO)5{PPhCl2}] with AgOSO2CF3 leads to the phosphine triflate complex [W(CO)5{PPhCl(OSO2CF3)}] 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 AgOSO2CF3 leads, in most cases, to the respective phosphine triflates [W(CO)5{PPhR(OSO2CF3)}], which react with ferrocene to form the ferrocenyl phosphine complexes [W(CO)5{PPhR(C10H9Fe)}]. The W(CO)5 unit can be removed via photolysis in the presence of bis(diphenylphosphino)ethane to form metal-free phosphines.

SUBMITTER: Jayaraman A

PROVIDER: S-EPMC6645012 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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

Jayaraman Arumugam A Nilewar Shrikant S Jacob Tyler V TV Sterenberg Brian T BT

ACS omega 20171114 11

ion of chloride from [W(CO)5{PPhCl2}] with AgOSO2CF3 leads to the phosphine triflate complex [W(CO)5{PPhCl(OSO2CF3)}] 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}], whe ...[more]

PMID: 31457342

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