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Iridium-catalyzed kinetic asymmetric transformations of racemic allylic benzoates.

ABSTRACT: Versatile methods for iridium-catalyzed, kinetic asymmetric substitution of racemic, branched allylic esters are reported. These reactions occur with a variety of aliphatic, aryl, and heteroaryl allylic benzoates to form the corresponding allylic substitution products in high yields (74-96%) with good to excellent enantioselectivity (84-98% ee) with a scope that encompasses a range of anionic carbon and heteroatom nucleophiles. These kinetic asymmetric processes occur with distinct stereochemical courses for racemic aliphatic and aromatic allylic benzoates, and the high reactivity of branched allylic benzoates enables enantioselective allylic substitutions that are slow or poorly selective with linear allylic electrophiles.

SUBMITTER: Stanley LM

PROVIDER: S-EPMC2909832 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Iridium-catalyzed kinetic asymmetric transformations of racemic allylic benzoates.

Stanley Levi M LM Bai Chen C Ueda Mitsuhiro M Hartwig John F JF

Journal of the American Chemical Society 20100701 26

Versatile methods for iridium-catalyzed, kinetic asymmetric substitution of racemic, branched allylic esters are reported. These reactions occur with a variety of aliphatic, aryl, and heteroaryl allylic benzoates to form the corresponding allylic substitution products in high yields (74-96%) with good to excellent enantioselectivity (84-98% ee) with a scope that encompasses a range of anionic carbon and heteroatom nucleophiles. These kinetic asymmetric processes occur with distinct stereochemica ...[more]

PMID: 20552969

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