Iridium-Catalyzed Asymmetric Allylations

Significance

The Grignard Nozaki-Hiyama allyl­ation of aldehydes is one of the most straightforward means to construct homoallylic alcohols. There has been a concerted effort by the synthetic community to provide asymmetric variants of this transformation. The Krische group has demonstrated that transfer hydrogenation is a versatile means to apply alcohols (as precursors to aldehydes) and π-unsaturated reactants in enantio­selective allylations. It is remarkable that electrophiles in the alcohol oxidation state can be utilized without the necessity of stoichiometric metal reductants.