Nhc-Catalyzed Aza-Benzoin Condensation Of N,N'-Dipyridin-2-Yl Aminals With Aldehydes

alpha-Amino ketones are useful compounds because of their synthetic utility and bioactivities. After observing the ability of N,N'-dipyridin-2-yl aminals to form imines in situ, the synthesis of a-amino ketones using N,N'-dipyridin-2-yl aminals was proposed. Through the NHC-catalyzed aza-benzoin reaction between aromatic/aliphatic aldehydes and N,N'-dipyridin-2-yl aminals, alpha-amino ketones, including aromatic, heterocyclic, and aliphatic versions, were synthesized with yields up to 99%. A direct route toward N-Boc-protected alpha-amino ketones from N,N,N'-tris-Boc aminals was also discovered, yielding the desired N-Boc-protected alpha-amino ketones in yields up to 73%.