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Pd(II)-catalyzed hydroxyl-directed C-H olefination enabled by monoprotected amino acid ligands.

ABSTRACT: A novel Pd(II)-catalyzed ortho-C-H olefination protocol has been developed using spatially remote, unprotected tertiary, secondary, and primary alcohols as the directing groups. Mono-N-protected amino acid ligands were found to promote the reaction, and an array of olefin coupling partners could be used. When electron-deficient alkenes were used, the resulting olefinated intermediates underwent subsequent Pd(II)-catalyzed oxidative intramolecular cyclization to give the corresponding pyran products, which could be converted into ortho-alkylated alcohols under hydrogenolysis conditions. The mechanistic details of the oxidative cyclization step are discussed and situated in the context of the overall catalytic cycle.

SUBMITTER: Lu Y

PROVIDER: S-EPMC2882203 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Pd(II)-catalyzed hydroxyl-directed C-H olefination enabled by monoprotected amino acid ligands.

Lu Yi Y Wang Dong-Hui DH Engle Keary M KM Yu Jin-Quan JQ

Journal of the American Chemical Society 20100401 16

A novel Pd(II)-catalyzed ortho-C-H olefination protocol has been developed using spatially remote, unprotected tertiary, secondary, and primary alcohols as the directing groups. Mono-N-protected amino acid ligands were found to promote the reaction, and an array of olefin coupling partners could be used. When electron-deficient alkenes were used, the resulting olefinated intermediates underwent subsequent Pd(II)-catalyzed oxidative intramolecular cyclization to give the corresponding pyran produ ...[more]

PMID: 20359184

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