text: In 2008, simultaneous publications described the allylic C-H alkylation of  substrates.  These reactions were catalyzed by the White catalyst or by an earlier version of the complex bearing benzyl substituents on the sulfoxide in place of phenyl.  It was demonstrated that an additional sulfoxide ligand, dimethylsulfoxide (DMSO), was essential for promoting functionalization of the π-allyl intermediate; the bis-sulfoxide ligand alone was unable to complete the catalytic cycle.