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Pd-catalyzed asymmetric ?-hydride elimination en route to chiral allenes.

ABSTRACT: We wish to report our preliminary results on the discovery and development of a catalytic, asymmetric ?-hydride elimination from vinyl Pd(II)-complexes derived from enol triflates to access chiral allenes. To achieve this, we developed a class of chiral phosphite ligands that demonstrate high enantioselectivity, allow access of either allene enantiomer, and are readily synthesized. The methodology is demonstrated on over 20 substrates, and application to the formal asymmetric total synthesis of the natural product, (+)-epibatidine, is also provided.

SUBMITTER: Crouch IT

PROVIDER: S-EPMC3758424 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Pd-catalyzed asymmetric β-hydride elimination en route to chiral allenes.

Crouch Ian T IT Neff Robynne K RK Frantz Doug E DE

Journal of the American Chemical Society 20130319 13

We wish to report our preliminary results on the discovery and development of a catalytic, asymmetric β-hydride elimination from vinyl Pd(II)-complexes derived from enol triflates to access chiral allenes. To achieve this, we developed a class of chiral phosphite ligands that demonstrate high enantioselectivity, allow access of either allene enantiomer, and are readily synthesized. The methodology is demonstrated on over 20 substrates, and application to the formal asymmetric total synthesis of ...[more]

PMID: 23488914

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