The Catalytic Asymmetric α‐Benzylation of Aldehydes

The first aminocatalyzed α‐alkylation of α‐branched aldehydes with benzyl bromides as alkylating agents has been developed. Using a sterically demanding proline derived catalyst, racemic α‐branched aldehydes are reacted with alkylating agents in a DYKAT process to give the corresponding α‐alkylated aldehydes with quaternary stereogenic centers in good yields and high enantioselectivities.