Allylic ruthenium(IV) complexes in catalysis

Two types of allylic ruthenium(IV) complexes. Two families of ruthenium catalysts with wide applications. [Display omitted] ► Applications of bis(allyl)ruthenium(IV) complexes in various catalytic transformations. ► (Allyl)ruthenium(IV) catalysts for allylation of nucleophiles. ► Miscellaneous reactions involving allylic ruthenium(IV) species. This review presents recent advances in the use of allylic ruthenium(IV) complexes as precatalysts in transition metal-catalyzed reactions. The topic is dominated by nucleophilic substitution reactions, where they appear either as initial catalysts or are generated upon oxidative addition of allylic substrates to ruthenium(II) precatalysts. Indeed, the general catalytic cycle describing this reaction is based on Ru(II)/Ru(IV) alternance. Other applications of allylic complexes, especially bis(allyl)Ru(IV) complexes in various catalytic transformations are also reported.