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Synthesis of substituted chromanones: an organocatalytic aldol/oxa-Michael reaction.

ABSTRACT: A diastereoselective organocatalytic aldol/oxa-Michael reaction has been developed to efficiently deliver medicinally relevant 2,3-ring-substituted chromanones. Development of this synthetic strategy revealed an unexpected kinetic anti-Saytzeff elimination; an origin for the observed selectivity is suggested on the basis of the results of quantum chemical calculations. This unusual kinetic selectivity necessitated an isomerization protocol that in turn led to the discovery of an intriguing Pd-mediated isomerization/intramolecular Friedel-Crafts-type alkylation.

SUBMITTER: Butler JD

PROVIDER: S-EPMC3164863 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

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Synthesis of substituted chromanones: an organocatalytic aldol/oxa-Michael reaction.

Butler Jeffrey D JD Conrad Wayne E WE Lodewyk Michael W MW Fettinger James C JC Tantillo Dean J DJ Kurth Mark J MJ

Organic letters 20100801 15

A diastereoselective organocatalytic aldol/oxa-Michael reaction has been developed to efficiently deliver medicinally relevant 2,3-ring-substituted chromanones. Development of this synthetic strategy revealed an unexpected kinetic anti-Saytzeff elimination; an origin for the observed selectivity is suggested on the basis of the results of quantum chemical calculations. This unusual kinetic selectivity necessitated an isomerization protocol that in turn led to the discovery of an intriguing Pd-me ...[more]

PMID: 20617821

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