Intermolecular hydroacylation by transition-metal complexes

In this review, transition-metal-catalyzed intermolecular hydroacylation, which is a direct synthetic protocol generating ketones from aldehydes and unsaturated hydrocarbons, will be discussed. In order to avoid decarbonylation, one of the major side-reactions occurring in transition-metal-catalyzed hydroacylation, several important strategies have been developed: An aldehyde ligand bearing a coordinating heteroatom at an appropriate position, a chelation auxiliary, and a masked form of the aldehyde, such as an aldimine or allylamine. Hydroacylation or its variations can also be applied to the synthesis of cycloalkanones and an α,β-unsaturated ketone or to the carbon-carbon triple bond cleavage of an alkyne.