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Enantioselective synthesis of bicylco[3.2.1]octan-8-ones using a tandem Michael-Henry reaction.

ABSTRACT: Bicyclo[3.2.1]octan-8-ones have been prepared from a tandem Michael-Henry reaction between cyclohexane-1,2-diones and nitroalkenes using a quinine-derived thiourea as the catalyst. Although four stereogenic centers were created during the reaction, only two diastereomers were obtained in good diastereoselectivity and high enantioselectivity (92-99% ee). When 3-methylcyclohexane-1,2-dione (R(1) = Me) was used as the substrate, only the regioisomeric product of the corresponding thermodynamic enolate was obtained.

SUBMITTER: Ding D

PROVIDER: S-EPMC2880813 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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Enantioselective synthesis of bicylco[3.2.1]octan-8-ones using a tandem Michael-Henry reaction.

Ding Derong D Zhao Cong-Gui CG Guo Qunsheng Q Arman Hadi H

Tetrahedron 20100601 25

Bicyclo[3.2.1]octan-8-ones have been prepared from a tandem Michael-Henry reaction between cyclohexane-1,2-diones and nitroalkenes using a quinine-derived thiourea as the catalyst. Although four stereogenic centers were created during the reaction, only two diastereomers were obtained in good diastereoselectivity and high enantioselectivity (92-99% ee). When 3-methylcyclohexane-1,2-dione (R(1) = Me) was used as the substrate, only the regioisomeric product of the corresponding thermodynamic enol ...[more]

PMID: 20532185

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