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Application of a chiral scaffolding ligand in catalytic enantioselective hydroformylation.

ABSTRACT: The synthesis of ?-amino-aldehydes has been achieved through enantioselective hydroformylation of PMP-protected allylic amines. The reaction is accomplished by using a scalemic scaffolding ligand that covalently and reversibly binds to the substrate. These ligands behave like chiral auxiliaries because they are covalently attached to the substrate during hydroformylation; however, similar to traditional asymmetric ligands, they can be used in catalytic quantities. The directed hydroformylation of disubstituted olefins occurs under mild conditions (35 °C and 50 psi CO/H(2)), and Z-olefins afford excellent enantioselectivities (up to 93% ee).

SUBMITTER: Worthy AD

PROVIDER: S-EPMC2962579 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Application of a chiral scaffolding ligand in catalytic enantioselective hydroformylation.

Worthy Amanda D AD Joe Candice L CL Lightburn Thomas E TE Tan Kian L KL

Journal of the American Chemical Society 20101001 42

The synthesis of β-amino-aldehydes has been achieved through enantioselective hydroformylation of PMP-protected allylic amines. The reaction is accomplished by using a scalemic scaffolding ligand that covalently and reversibly binds to the substrate. These ligands behave like chiral auxiliaries because they are covalently attached to the substrate during hydroformylation; however, similar to traditional asymmetric ligands, they can be used in catalytic quantities. The directed hydroformylation o ...[more]

PMID: 20882977

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