Enolizable Carbonyls and N,O‐Acetals: A Rational Approach for Room‐Temperature Lewis Superacid‐Catalyzed Direct α‐Amidoalkylation of Ketones and Aldehydes.

An efficient catalytic room-temperature direct α-amidoalkylation of carbonyl donors, that is, ketones and aldehydes with unbiased N,O-acetals, is described. Sn(NTf2 )4 is an optimal catalyst to promote this challenging transformation at low loading and the reaction shows promising scope. A comprehensive and rational evaluation of this reaction has led to the establishment of an empirical scale of nucleophilic reactivity for a broad set of ketones that should be helpful in the synthetic design and development of carbonyl α-functionalization methods.