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Simple chiral diene ligands provide high enantioselectivities in transition-metal-catalyzed conjugate addition reactions.

ABSTRACT: Chiral dienes possessing the bicyclo[2.2.2]octadiene framework were prepared readily through the [4 + 2] cycloaddition of ( R)-alpha-phellandrene with methyl propiolate as the key step. Diene 9, substituted with a tertiary alcohol on one of the two double bonds, is prepared in just one step from the cycloadduct and is highly effective as a chiral ligand for rhodium-catalyzed asymmetric conjugate addition reactions, giving the corresponding addition products with higher enantioselectivity than other chiral dienes.

SUBMITTER: Okamoto K

PROVIDER: S-EPMC2666791 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Simple chiral diene ligands provide high enantioselectivities in transition-metal-catalyzed conjugate addition reactions.

Okamoto Kazuhiro K Hayashi Tamio T Rawal Viresh H VH

Organic letters 20080905 19

Chiral dienes possessing the bicyclo[2.2.2]octadiene framework were prepared readily through the [4 + 2] cycloaddition of ( R)-alpha-phellandrene with methyl propiolate as the key step. Diene 9, substituted with a tertiary alcohol on one of the two double bonds, is prepared in just one step from the cycloadduct and is highly effective as a chiral ligand for rhodium-catalyzed asymmetric conjugate addition reactions, giving the corresponding addition products with higher enantioselectivity than ot ...[more]

PMID: 18771267

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