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Rh(III)-Catalyzed Diastereoselective C-H Bond Addition/Cyclization Cascade of Enone Tethered Aldehydes.

ABSTRACT: The Rh(III)-catalyzed cascade addition of a C-H bond across alkene and carbonyl π-bonds is reported. The reaction proceeds under mild reaction conditions with low catalyst loading. A range of directing groups were shown to be effective as was the functionalization of alkenyl in addition to aromatic C(sp²)-H bonds. When the enone and aldehyde electrophile were tethered together, cyclic β-hydroxy ketones with three contiguous stereocenters were obtained with high diastereoselectivity. The intermolecular three-component cascade reaction was demonstrated for both aldehyde and imine electrophiles. Moreover, the first x-ray structure of a cationic Cp*Rh(III) enolate with interatomic distances consistent with an η³-bound enolate is reported.

SUBMITTER: Boerth JA

PROVIDER: S-EPMC4762265 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Rh(III)-Catalyzed Diastereoselective C-H Bond Addition/Cyclization Cascade of Enone Tethered Aldehydes.

Boerth Jeffrey A JA Ellman Jonathan A JA

Chemical science 20151201 2

The Rh(III)-catalyzed cascade addition of a C-H bond across alkene and carbonyl π-bonds is reported. The reaction proceeds under mild reaction conditions with low catalyst loading. A range of directing groups were shown to be effective as was the functionalization of alkenyl in addition to aromatic C(sp<sup>2</sup>)-H bonds. When the enone and aldehyde electrophile were tethered together, cyclic β-hydroxy ketones with three contiguous stereocenters were obtained with high diastereoselectivity. T ...[more]

PMID: 26918112

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