Copper‐Catalyzed Enantioselective Allylic Substitution with Readily Accessible Carbonyl‐ and Acetal‐Containing Vinylboron Reagents.

Catalytic enantioselective allylic substitution (EAS) reactions are of prominent utility in chemical synthesis.[i] Such transformations generate a stereogenic center adjacent to an alkene, which can be further functionalized to afford a range of other enantiomerically enriched molecules. Despite noteworthy advances, several issues remain unresolved in this area. Nearly all the existing protocols require nucleophilic metal-based reagents, which, while often the source of high reactivity, are not well suited when certain commonly occurring functional groups are present. Moreover, whereas significant focus has been placed on additions of alkyl groups,[i] reported examples of catalytic processes that lead to incorporation of aryl or heteroaryl,[ii] allyl,[iii] alkynyl[iv] or allenyl[v] moieties are markedly small in number.