Copper mediated A3-coupling reaction for the preparation of enantioselective deoxy sugar based chiral propargylamines using bifunctional ligand l-proline. (August 2020) - Thakur, Kratima
Abstract: An efficient three component coupling of aromatic aldehyde, deoxy sugar based alkyne ( α -2-deoxy propargyl glycoside) and heterocyclic amine have been refluxed to synthesize stereoselective chiral propargylamines with good to excellent yield using only CuI catalyst along with bifunctional ligand l -proline. This method has proved to be applicable in wide range of substrates and found highly enantioselective with respect to earlier reported methods. In addition, l -proline was found as a chiral source which demonstrated that it could be developed as a highly enantioselective method for the construction of deoxy sugar based chiral propargylamines. The ligand l -proline was used for the first time in enantioselective A 3 -coupling reaction of α -2-deoxy propargyl glycosides involving substituted aromatic aldehyde and heterocyclic amines. Herein, we have synthesized 15 novel compounds based on A 3 -coupling reaction and structures of all the enantioselective compounds were characterised by TLC and NMR spectroscopy. Graphical abstract: Image 1 Highlights: Developing new method for the synthesis of deoxy sugar based chiral propargylamine. l -proline was used as bifunctional ligation. Acetylenic C–H bond activation.