title: Copper-catalyzed enantioselective additions to oxocarbenium ions: alkynylation of isochroman acetals.
abstract: We have developed an enantioselective, copper(I)-catalyzed addition of terminal alkynes to racemic isochroman acetals. This method is one of the first transition-metal-catalyzed approaches to enantioselective additions to prochiral oxocarbenium ions. In this reaction, TMSOTf is used to form the oxocarbenium ion in situ under conditions compatible with simultaneous formation of the chiral copper acetylide. By using a bis(oxazoline) ligand, good yields and enantioselectivities are observed for a variety of enantioenriched 1-alkynyl isochromans.
authors: Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
authors: Prantik
authors: P
authors: Maity
authors: Harathi D
authors: HD
authors: Srinivas
authors: Mary P
authors: MP
authors: Watson
mesh_terms: D000080:Acetals / Q000737:chemistry*; D000480:Alkynes / Q000138:chemical synthesis* / Q000737:chemistry*; D002839:Chromans / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000080:Acetals; D000480:Alkynes; D002839:Chromans; D007477:Ions; D009942:Organometallic Compounds; D003300:Copper