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Diastereoselective synthesis of highly substituted cyclohexanones and tetrahydrochromene-4-ones via conjugate addition of curcumins to arylidenemalonates.

ABSTRACT: A cascade inter-intramolecular double Michael strategy for the synthesis of highly functionalized cyclohexanones from curcumins and arylidenemalonates is reported. This strategy works in the presence of aqueous KOH using TBAB as a suitable phase transfer catalyst at room temperature. The functionalized cyclohexanones are formed as major products in moderate to excellent yields with complete diastereoselectivity in most cases. A triple Michael adduct, tetrahydrochromen-4-one, is also formed as a side product in a few cases with excellent diastereoselectivity.

SUBMITTER: Nair D

PROVIDER: S-EPMC11331540 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature

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Diastereoselective synthesis of highly substituted cyclohexanones and tetrahydrochromene-4-ones via conjugate addition of curcumins to arylidenemalonates.

Nair Deepa D Tiwari Abhishek A Laha Banamali B Namboothiri Irishi N N INN

Beilstein journal of organic chemistry 20240815

A cascade inter-intramolecular double Michael strategy for the synthesis of highly functionalized cyclohexanones from curcumins and arylidenemalonates is reported. This strategy works in the presence of aqueous KOH using TBAB as a suitable phase transfer catalyst at room temperature. The functionalized cyclohexanones are formed as major products in moderate to excellent yields with complete diastereoselectivity in most cases. A triple Michael adduct, tetrahydrochromen-4-one, is also formed as a ...[more]

PMID: 39161707

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