Transition metal-mediated P-C/X exchange at bound phosphine ligands (X=aryl, alkyl, NR2, OR and F): scope and mechanisms.

The range of transition metal-mediated P-C/X exchange reactions that result in the replacement of a phosphine substituent with another group, X, are categorised according to the nature of the replacing group (X=aryl or alkyl, N- and O-based species and fluoride). Proposed mechanisms for P-C/X exchange are described and the factors promoting these unusual-and often undesirable-reactions are discussed. This tutorial review should be of relevance for those engaged in homogeneous catalysis, C-F activation and the synthesis of complexes combining soft metal centres and hard donor ligands.