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Ruthenium(ii)-catalyzed regioselective 1,6-conjugate addition of umpolung aldehydes as carbanion equivalents.

ABSTRACT: One of the most efficient and reliable approaches to construct C-C bonds involves the conjugate addition of carbon nucleophiles to electron-deficient ketones. Yet, 1,6-conjugate additions of extended conjugated systems largely remain underexplored due to difficulties in controlling the regioselectivity. Herein, we report umpolung aldehydes as carbanion equivalents for highly regioselective 1,6-conjugate addition reactions to unsaturated ketones, with preliminary studies of the enantioselective variant. The synergy of ruthenium(ii) catalyst and electron-rich, bidentate phosphine ligand is essential for the reactivity and selectivity under mild reaction conditions.

SUBMITTER: Kang H

PROVIDER: S-EPMC8694324 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Ruthenium(ii)-catalyzed regioselective 1,6-conjugate addition of umpolung aldehydes as carbanion equivalents.

Kang Hyotaik H Li Chao-Jun CJ

Chemical science 20211129 1

One of the most efficient and reliable approaches to construct C-C bonds involves the conjugate addition of carbon nucleophiles to electron-deficient ketones. Yet, 1,6-conjugate additions of extended conjugated systems largely remain underexplored due to difficulties in controlling the regioselectivity. Herein, we report umpolung aldehydes as carbanion equivalents for highly regioselective 1,6-conjugate addition reactions to unsaturated ketones, with preliminary studies of the enantioselective v ...[more]

PMID: 35059159

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