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One-pot synthesis of enantiopure syn-1,3-diacetates from racemic syn/anti mixtures of 1,3-diols by dynamic kinetic asymmetric transformation.

ABSTRACT: A one-pot synthesis of enantiomerically pure syn-1,3-diacetates starting from readily accessible racemic diastereomeric mixtures of 1,3-diols has been realized by combining (i) enzymatic transesterification, (ii) ruthenium-catalyzed epimerization of a secondary alcohol in a diol or diol monoacetate, and (iii) intramolecular acyl migration in a syn-1,3-diol monoacetate. The in situ coupling of these three processes results in an efficient enantioselective synthesis of acyclic syn-1,3-diacetates via combined deracemization-deepimerization and constitutes a dynamic kinetic asymmetric transformation concept. Several differently substituted unsymmetrical, acyclic syn-1,3-diacetates were obtained in yields up to 73% with excellent enantioselectivities (>99%) and good diastereomeric ratios (>90% syn).

SUBMITTER: Edin M

PROVIDER: S-EPMC395981 | biostudies-literature | 2004 Apr

REPOSITORIES: biostudies-literature

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One-pot synthesis of enantiopure syn-1,3-diacetates from racemic syn/anti mixtures of 1,3-diols by dynamic kinetic asymmetric transformation.

Edin Michaela M Steinreiber Johannes J Bäckvall Jan-E JE

Proceedings of the National Academy of Sciences of the United States of America 20040406 16

A one-pot synthesis of enantiomerically pure syn-1,3-diacetates starting from readily accessible racemic diastereomeric mixtures of 1,3-diols has been realized by combining (i) enzymatic transesterification, (ii) ruthenium-catalyzed epimerization of a secondary alcohol in a diol or diol monoacetate, and (iii) intramolecular acyl migration in a syn-1,3-diol monoacetate. The in situ coupling of these three processes results in an efficient enantioselective synthesis of acyclic syn-1,3-diacetates v ...[more]

PMID: 15069194

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