Cesium salts as superior catalysts for solvent-free modifications of biosourced pterolactam

Abstract γ-Lactam derivatives are widespread biologically active compounds, covering a large range of activities. Following our interest in both medicinal and green chemistries, we developed an original, cesium salts-mediated, scalable and solvent-free methodology to transform biosourced pyroglutamic acid and its derivatives to their N,N ′-aminals, N,O , N,S -acetals and C 5 -substituted γ-lactams in good to excellent yields. This protocol is applicable to a large range of substrates, conducting to C 5 -substituted γ-lactam derivatives as potential new biologically active compounds.