A convenient stereoselective synthesis of 5-hydroxy-3-oxoesters and 3-hydroxy-5-oxoesters. Issue 6 (15th June 2017)

• Record Type: Journal Article
• Authors: Żądło-Dobrowolska, Anna; Schrittwieser, Joerg H.; Grischek, Barbara; Koszelewski, Dominik; Kroutil, Wolfgang; Ostaszewski, Ryszard
• Is Part Of: Tetrahedron, asymmetry. Volume 28:Issue 6(2017)
• Page Start: 797
• Page End: 802
• Publication Date: 2017-06-15
• Subjects: Asymmetry (Chemistry) -- Periodicals; 547.005
• DOI: 10.1016/j.tetasy.2017.05.005
• Languages: English
• ISSNs: 0957-4166

Abstract

Graphical abstract: Abstract: A biocatalytic approach was employed for the asymmetric reduction of sterically demanding ketones to prepare 3-hydroxy-5-oxo-5-phenylpentanoates and 5-hydroxy-3-oxo-5-phenylpentanoates. Screening a collection of microorganisms led to the identification of stereocomplementary microbial strains that provide access to both enantiomers of 3-hydroxy-5-oxo-5-phenylpentanoates and 5-hydroxy-3-oxo-5-phenylpentanoates with high enantiomeric excess (up to 99% ee ). Moreover, the application of Saccharomyces cerevisiae gave two diastereomers of 3, 5-dihydroxy-5-phenylpentanoates with high enantiomeric excess (up to 99% ee ). The applicability of the identified strains was demonstrated by transforming the obtained dihydroxy ester into the chemically valuable lactone (4 S, 6 R )-tetrahydro-4-hydroxy-6-phenyl-pyran-2-one. Abstract : Ethyl (3 R )-hydroxy-5-oxo-5-phenylpentanoate: C13 H16 O4 E.e. >99% [ α ]D = +17.5 ( c 0.75, CHCl3 ) Source of chirality: enzymatic reduction Absolute configuration: ( R ) Abstract : Ethyl (5 S )-hydroxy-3-oxo-5-phenylpentanoate: C13 H16 O4 E.e. = 72% [ α ]D = −36.6 ( c 0.75, CHCl3 ) Source of chirality: enzymatic reduction Absolute configuration: ( S ) Abstract : Ethyl (3 S, 5 R )-3, 5-dihydroxy-5-phenylpentanoate: C13 H18 O4 E.e. = 99% [ α ]D = +17.5 ( c 0.75, CHCl3 ) Source of chirality: enzymatic reduction Absolute configuration: (3 S, 5 R ) Abstract : t -Butyl (3 R )-hydroxy-5-oxo-5-phenylpentanoate: C15 H20 O4 E.e. = 93% [ α ]D = +13.6 ( c 0.28, CHCl3 ) Source of chirality: enzymatic reduction Absolute configuration: ( R ) Abstract : (4 S, 6 R )-Tetrahydro-4-hydroxy-6-phenyl-pyran-2-one: C11 H12 O3 E.e. = 98% [ α ]D = +9.9 ( c 0.89, CHCl3 ) Source of chirality: chemoenzymatic reaction Absolute configuration: (4 S, 6 R ) Abstract : t -Butyl (5 R )-hydroxy-3-oxo-5-phenylpentanoate: C15 H20 O4 E.e. = 80% [ α ]D = −26.6 ( c 1.15, CHCl3 ) Source of chirality: enzymatic reduction Absolute configuration: ( R )