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Divergent stereocontrol of acid catalyzed intramolecular aldol reactions of 2,3,7-triketoesters: synthesis of highly functionalized cyclopentanones.

ABSTRACT: The intramolecular acid catalyzed aldol cyclization of 2,3,7-triketoesters formed from ?-keto-?-diazo-?-ketoesters provides highly functionalized cyclopentanones with good diastereoselectivity in high overall yields via kinetically controlled and stereodivergent catalytic processes. Lewis acid catalysis gives high selectivity for the 1,2-anti tetrasubstituted cyclopentanones, whereas Brønsted acid catalysis produces the corresponding 1,2-syn diastereomer.

SUBMITTER: Truong P

PROVIDER: S-EPMC3480983 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Divergent stereocontrol of acid catalyzed intramolecular aldol reactions of 2,3,7-triketoesters: synthesis of highly functionalized cyclopentanones.

Truong Phong P Shanahan Charles S CS Doyle Michael P MP

Organic letters 20120628 14

The intramolecular acid catalyzed aldol cyclization of 2,3,7-triketoesters formed from ζ-keto-α-diazo-β-ketoesters provides highly functionalized cyclopentanones with good diastereoselectivity in high overall yields via kinetically controlled and stereodivergent catalytic processes. Lewis acid catalysis gives high selectivity for the 1,2-anti tetrasubstituted cyclopentanones, whereas Brønsted acid catalysis produces the corresponding 1,2-syn diastereomer. ...[more]

PMID: 22738671

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