10.1021/ja710689c.s007 Petteri Elsner Petteri Elsner Luca Bernardi Luca Bernardi Giorgio Dela Salla Giorgio Dela Salla Jacob Overgaard Jacob Overgaard Karl Anker Jørgensen Karl Anker Jørgensen Organocatalytic Asymmetric Conjugate Addition to Allenic Esters and Ketones American Chemical Society 2008 ketoester Glycine imine derivatives substituent glycine imine derivatives yield enantioselectivitie conjugate addition organocatalytic enantioselective conjugate addition chiral ee cyclic Organocatalytic Asymmetric Conjugate Addition allene ester 2008-04-09 00:00:00 Dataset https://acs.figshare.com/articles/dataset/Organocatalytic_Asymmetric_Conjugate_Addition_to_Allenic_Esters_and_Ketones/2945749 The first example of an organocatalytic enantioselective conjugate addition of cyclic β-ketoesters and glycine imine derivatives to electron-deficient allenes is described. We disclose that the corresponding chiral β,γ-unsaturated carbonyl compounds are formed exclusively under phase-transfer conditions using either cinchona-alkaloid-derived or biphenyl-based chiral quaternary ammonium salts as catalysts. The scope of the reaction for β-ketoesters is outlined for allenes having a ketone or ester motif as electron-withdrawing group as well as different substituents in the 3-position, giving the optically active products in high yields and excellent diastereo- and enantioselectivities (90−96% ee). The conjugate addition also proceeds for a number of cyclic β-ketoesters having different ring sizes, ring systems, and substituents in high yields and enantioselectivities. Glycine imine derivatives also undergo the asymmetric conjugate addition to electron-deficient allenes in high yields and with enantioselectivities in the range of 60−88% ee, thus providing a rapid entry to optically active α-vinyl-substituted α-amino acid derivatives. It is shown that the enantioselectivity is strongly dependent on the size of the ester moiety of the nucleophile in combination with the catalytic system used. The high synthetic value of the chiral products arising from these new catalytic processes is demonstrated by two straightforward transformations leading in one case to optically active hexahydrobenzopyranones and in the other to substituted pyroglutamates (γ-lactames).