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Rhodium-catalyzed intermolecular enantioselective Alder–ene type reaction of cyclopentenes with silylacetylenes

ABSTRACT: The Alder–ene type reaction between alkenes and alkynes provides an efficient and atom-economic method for the construction of C-C bond, which has been widely employed in the synthesis of natural products and other functional molecules. The intramolecular enantioselective Alder-ene cycloisomerization reactions of 1,n-enynes have been extensively investigated. However, the intermolecular asymmetric version has not been reported, and remains a challenging task. Herein, we describe a rhodium-catalyzed intermolecular enantioselective Alder-ene type reaction of cyclopentenes with silylacetylenes. A variety of chiral (E)-vinylsilane tethered cyclopentenes bearing one quaternary carbon and one tertiary carbon stereocenters are achieved in high yields and enantioselectivities. The reaction undergoes carbonyl-directed migratory insertion, β-H elimination and desymmetrization of prochiral cyclopentenes processes. The Alder–ene type reaction is a synthetically useful, redox-neutral method to rearrange carbon–carbon bonds, but has only been demonstrated intramolecularly. Here the authors present a method to perform the Alder–ene type reaction intermolecularly with cylcopentenes and silylynes, proceeding enantioselectively via rhodium catalysis.

SUBMITTER: Zhang D

PROVIDER: S-EPMC8595345 | biostudies-literature |

REPOSITORIES: biostudies-literature

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