Calcium(II)-Catalyzed Reductive Amination of Biomass-Derived Keto Acids to Functionalized Lactams under Solvent-Free Conditions

Abstract

Direct access to the polyfluorinated lactams through Ca(NTf 2 ) 2 catalyzed by either the reductive amination of biomass-derived keto acids with amines or the reductive amination of amino acids with carbonyl derivatives under solvent-free conditions is realized. The two versatile protocols display chemospecificity and good substrate tolerance to deliver five-to eight-membered lactams with diverse functionality and substitution patterns. The robustness of the methodology is further demonstrated by subsequent application in the late-stage functionalization of drug molecules.

Calcium(II)-Mediated Three-Component Selenofunctionalization of Alkenes under Mild Conditions

“…Nigemann, Gandon, McLaughlin, and others have demonstrated the high efficacy of calcium complexes in catalyzing a range of transformations. In light of this, our research group has a growing fascination with the exploration and development of new synthetic methods that utilize calcium complexes as Lewis acid catalysts . Enthused by these studies and drawing inspiration from the incorporation of N-PSP as an effector, we hypothesized that a system based on Ca­(NTf 2 ) 2 could effectively activate N-PSP through chelation to the amide carbonyl group.…”