title: Enantioselective redox-neutral Rh-catalyzed coupling of terminal alkynes with carboxylic acids toward branched allylic esters.
abstract: We report on the first enantioselective variant of the atom-economic and redox-neutral coupling of carboxylic acids with terminal alkynes under rhodium catalysis utilizing the chiral, bidentate (R,R)-Cp-DIOP ligand. This represents the first example of this convenient asymmetric access to valuable branched allylic esters. The utility of this methodology is demonstrated by both a reaction performed on large scale and a short three-step synthesis of two naturally occurring γ-butyrolactones. A stereochemical model explaining the observed absolute configuration of the products based on DFT calculations is given.
authors: Institut für Organische Chemie, Albert-Ludwigs-Universität Freiburg , Albertstraße 21, 79104 Freiburg im Breisgau, Germany.
authors: Philipp
authors: P
authors: Koschker
authors: Matthias
authors: M
authors: Kähny
authors: Bernhard
authors: B
authors: Breit