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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.

SUBMITTER: Maity P

PROVIDER: S-EPMC4203715 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Copper-catalyzed enantioselective additions to oxocarbenium ions: alkynylation of isochroman acetals.

Maity Prantik P Srinivas Harathi D HD Watson Mary P MP

Journal of the American Chemical Society 20111011 43

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 v ...[more]

PMID: 21988178

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