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Enantioselective intramolecular hydroarylation of alkenes via directed C-H bond activation.

ABSTRACT: Highly enantioselective catalytic intramolecular ortho-alkylation of aromatic imines containing alkenyl groups tethered at the meta position relative to the imine directing group has been achieved using [RhCl(coe)2]2 and chiral phosphoramidite ligands. Cyclization of substrates containing 1,1- and 1,2-disubstituted as well as trisubstituted alkenes were achieved with enantioselectivities >90% ee for each substrate class. Cyclization of substrates with Z-alkene isomers proceeded much more efficiently than substrates with E-alkene isomers. This further enabled the highly stereoselective intramolecular alkylation of certain substrates containing Z/E-alkene mixtures via a Rh-catalyzed alkene isomerization with preferential cyclization of the Z-isomer.

SUBMITTER: Harada H

PROVIDER: S-EPMC2610454 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

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Enantioselective intramolecular hydroarylation of alkenes via directed C-H bond activation.

Harada Hitoshi H Thalji Reema K RK Bergman Robert G RG Ellman Jonathan A JA

The Journal of organic chemistry 20080806 17

Highly enantioselective catalytic intramolecular ortho-alkylation of aromatic imines containing alkenyl groups tethered at the meta position relative to the imine directing group has been achieved using [RhCl(coe)2]2 and chiral phosphoramidite ligands. Cyclization of substrates containing 1,1- and 1,2-disubstituted as well as trisubstituted alkenes were achieved with enantioselectivities >90% ee for each substrate class. Cyclization of substrates with Z-alkene isomers proceeded much more efficie ...[more]

PMID: 18681407

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