title: Regio- and Enantioselective Rhodium-Catalyzed Addition of 1,3-Diketones to Allenes: Construction of Asymmetric Tertiary and Quaternary All Carbon Centers.
abstract: An unprecedented highly regio- and enantioselective rhodium-catalyzed addition of 1,3-diketones to terminal and 1,1-disubstituted allenes furnishing asymmetric tertiary and quaternary all-carbon centers is reported. By applying a RhI/phosphoramidite/TFA catalytic system under mild conditions, the desired chiral branched α-allylated 1,3-diketones could be obtained in good to excellent yields, with perfect regioselectivity and in high enantioselectivity. The reaction shows a broad functional-group tolerance on both reaction partners highlighting its synthetic potential.
authors.affiliation: Institut für Organische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstraße 21, 79104, Freiburg, Germany.
authors.forename: Thorsten M
authors.initials: TM
authors.lastname: Beck
authors.affiliation: Institut für Organische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstraße 21, 79104, Freiburg, Germany.
authors.forename: Bernhard
authors.identifier: 0000-0002-2514-3898
authors.initials: B
authors.lastname: Breit
keywords: 1,3-diketones; allenes; asymmetric catalysis; rhodium; γ,δ-unsaturated ketones