Phosphapalladacycles: preparation routes

The review considers methods of synthesis of cyclopalladated compounds of the PC- and PCP-type including intramolecular activation of the C–H bonds in the P-donor ligands, oxidative addition of preliminarily functionalised substrates to palladium(0), transmetallation of lithiated compounds, chelation of phosphine-substituted phosphorus ylides, and some non-standard processes resulting in a new ligand formation on a metal template. Particular attention has been given to the structural factors and experimental conditions that determine the feasibility of direct cyclopalladation of mono- and bidentate phosphines, phosphites and phosphinites.