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Stereoselective alkylation of alpha,beta-unsaturated imines via C-H bond activation.

ABSTRACT: The stereoselective alkylation of alpha,beta-unsaturated imines via C-H activation followed by imine hydrolysis produces tri- and tetrasubstituted alpha,beta-unsaturated aldehydes. In the presence of a rhodium catalyst, alpha,beta-unsaturated N-benzyl imines derived from methacrolein, crotonaldehyde, and tiglic aldehyde undergo directed C-H activation at the beta-position and react with terminal alkenes and alkynes to form the tri- and tetrasubstituted alpha,beta-unsaturated imines with very high stereoselectivity. Hydrolysis to provide alpha,beta-unsaturated aldehydes can be performed under carefully controlled conditions that maintain the stereochemistry of the beta-alkylated imine products. Alternatively, for beta-alkylation products of the N-benzyl imine of methacrolein, hydrolysis can be performed under conditions that provide complete isomerization to the E isomer.

SUBMITTER: Colby DA

PROVIDER: S-EPMC2585547 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature

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Stereoselective alkylation of alpha,beta-unsaturated imines via C-H bond activation.

Colby Denise A DA Bergman Robert G RG Ellman Jonathan A JA

Journal of the American Chemical Society 20060501 17

The stereoselective alkylation of alpha,beta-unsaturated imines via C-H activation followed by imine hydrolysis produces tri- and tetrasubstituted alpha,beta-unsaturated aldehydes. In the presence of a rhodium catalyst, alpha,beta-unsaturated N-benzyl imines derived from methacrolein, crotonaldehyde, and tiglic aldehyde undergo directed C-H activation at the beta-position and react with terminal alkenes and alkynes to form the tri- and tetrasubstituted alpha,beta-unsaturated imines with very hig ...[more]

PMID: 16637605

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