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Enantioselective synthesis of beta-(3-hydroxypyrazol-1-yl) ketones using an organocatalyzed Michael addition reaction.

ABSTRACT: Beta-(3-hydroxypyrazol-1-yl) ketones have been prepared in high yields and excellent enantioselectivities (94-98% ee) via a Michael addition reaction between 2-pyrazolin-5-ones and aliphatic acyclic alpha,beta-unsaturated ketones using 9-epi-9-amino-9-deoxyquinine as the catalyst. These results account for the first example of an aza-Michael addition of the ambident 2-pyrazolin-5-one anion to a Michael acceptor.

SUBMITTER: Gogoi S

PROVIDER: S-EPMC2752151 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Enantioselective synthesis of beta-(3-hydroxypyrazol-1-yl) ketones using an organocatalyzed Michael addition reaction.

Gogoi Sanjib S Zhao Cong-Gui CG Ding Derong D

Organic letters 20090601 11

Beta-(3-hydroxypyrazol-1-yl) ketones have been prepared in high yields and excellent enantioselectivities (94-98% ee) via a Michael addition reaction between 2-pyrazolin-5-ones and aliphatic acyclic alpha,beta-unsaturated ketones using 9-epi-9-amino-9-deoxyquinine as the catalyst. These results account for the first example of an aza-Michael addition of the ambident 2-pyrazolin-5-one anion to a Michael acceptor. ...[more]

PMID: 19415906

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