Synthesis and Chiroptical Properties of Some Piperidin-2-ones

Article abstract of DOI:10.1021/jo00349a005

The synthesis of optically pure (R)-(+)-4-isopropylpiperidin-2-one, (R)-(+)-4-isopropyl-4-methylpiperidin-2-one, and (R)-(+)-5-methylpiperidin-2-one in high yields from monocyclic terpene precursors are described.The CD spectra of these compounds are reported, and the chiroptical properties of δ-lactams are examined in terms of current theories for the amide chromophore.It is concluded that slight, conformationally induced nonplanarity of the amide chromophore is responsible for signs of the longest wavelenght bands in the CD spectra of these and related compounds.