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Chiral Ligands Based on Binaphthyl Scaffolds for Pd-Catalyzed Enantioselective C-H Activation/Cycloaddition Reactions.

ABSTRACT: We report the first examples of the use of a new class of ligands (NOBINAc) for performing asymmetric C-H activations using palladium catalysts. These ligands combine the axial chirality of binaphthyl scaffolds with the bifunctional and bidentate coordination properties of mono-N-protected amino acids (MPAAs), which are well-known to favor Pd-promoted C-H activations via concerted metalation-deprotonation mechanisms. We demonstrate that our new ligands enable substantially higher enantioselectivities than MPAAs in the assembly of 2-benzazepines through formal (5 + 2) cycloadditions between homobenzyltriflamides or o-methylbenzyltriflamides and allenes.

SUBMITTER: Gonzalez JM

PROVIDER: S-EPMC9716525 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Chiral Ligands Based on Binaphthyl Scaffolds for Pd-Catalyzed Enantioselective C-H Activation/Cycloaddition Reactions.

González José Manuel JM Vidal Xandro X Ortuño Manuel Angel MA Mascareñas José Luis JL Gulías Moisés M

Journal of the American Chemical Society 20221115 47

We report the first examples of the use of a new class of ligands (NOBINAc) for performing asymmetric C-H activations using palladium catalysts. These ligands combine the axial chirality of binaphthyl scaffolds with the bifunctional and bidentate coordination properties of mono-N-protected amino acids (MPAAs), which are well-known to favor Pd-promoted C-H activations via concerted metalation-deprotonation mechanisms. We demonstrate that our new ligands enable substantially higher enantioselectiv ...[more]

PMID: 36378026

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