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Enantioselective Intermolecular [2+2] Photocycloaddition Reaction of Cyclic Enones and Its Application in a Synthesis of (-)-Grandisol.

ABSTRACT: The intermolecular [2+2] photocycloaddition of typical cyclic ?,?-unsaturated enones, such as 2-cyclohexenone, with olefins was performed in moderate to good yields (42-82%) and with high enantioselectivity (82%-96% ee). An unusual substitution pattern at the chiral oxazaborolidine-AlBr3 Lewis acid complex that promotes the reaction was found to be crucial for the success of the reaction. The method was applied to the enantioselective synthesis of the monoterpene (-)-grandisol, which could be accomplished in six steps and with an overall yield of 13% starting from 3-methyl-2-cyclohexenone.

SUBMITTER: Poplata S

PROVIDER: S-EPMC5849358 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Enantioselective Intermolecular [2+2] Photocycloaddition Reaction of Cyclic Enones and Its Application in a Synthesis of (-)-Grandisol.

Poplata Saner S Bach Thorsten T

Journal of the American Chemical Society 20180222 9

The intermolecular [2+2] photocycloaddition of typical cyclic α,β-unsaturated enones, such as 2-cyclohexenone, with olefins was performed in moderate to good yields (42-82%) and with high enantioselectivity (82%-96% ee). An unusual substitution pattern at the chiral oxazaborolidine-AlBr<sub>3</sub> Lewis acid complex that promotes the reaction was found to be crucial for the success of the reaction. The method was applied to the enantioselective synthesis of the monoterpene (-)-grandisol, which ...[more]

PMID: 29458250

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