An anionic phosphenium complex as an ambident nucleophile

作者：Stadelmann B; Bender J; Foerster D; Frey W; Nieger M; Gudat D^*

来源：Dalton Transactions, 2015, 44(13): 6023-6031.

DOI：10.1039/c5dt00008d

A unique anionic phosphenium complex was prepared from reaction of an N-heterocyclic chlorophosphine with Collman's reagent or K[HFe(CO)(4)]/NaH and characterized by spectral and XRD data. The complex behaves as an ambident nucleophile. Reactions with acetic acid, ClSnPh3, and a further equivalent of an N-heterocyclic chlorophosphine proceed via electrophilic functionalization at the metal site to yield appropriate mono- or bis-phosphenium complexes. Reaction with MeI at -70 degrees C produces a P-alkylation product as the first spectroscopically detectable intermediate, which decays at a higher temperature to give a mixture of free P-methylated N-heterocyclic phosphine and its Fe(CO)(4) complex. The different reaction products were characterized by spectral and XRD data. Computational studies indicate that the NHP units in all complexes display p-acceptor behaviour but show no disposition to adopt phosphide-like character or formally oxidize the metal centre.

• 出版日期2015