| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1347811 | Tetrahedron: Asymmetry | 2013 | 9 Pages |
Eight racemic 1-(furan-2-yl)ethanols were prepared from the corresponding carbonyl compounds for enantioselective acylation studies, and seven of them were used in preparative-scale kinetic resolutions with Candida antarctica lipase B (Novozym 435) and vinyl acetate in dried diisopropyl ether. Mechanism-based competition between the (R)-acetate (enzymatic acylation product), vinyl acetate (added acylating reagent), and acetic acid (enzymatic hydrolysis product) toward CAL-B, together with the residual water of the lipase were shown to be potential reasons for side reactions, which affected the course of the kinetic resolution of 1-[5-(2-chlorophenyl) and (4-bromophenyl)furan-2-yl]ethanols. Clear effects were not observed with the other alcoholic substrates. Alcoholysis of the enantiomerically enriched (R)-acetates with methanol and CAL-B in diisopropyl ether was shown to be a potential method for the deprotection of the (R)-acetates and the formation of (R)-alcohols.
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(S)-1-(Furan-2-yl)ethanolC6H8O2[α]D25=-20.8 (c 1.0, CHCl3)ee = 98% on Chrompack CP-Chirasil-DEX CB GC columnSource of chirality: enzymatic resolutionAbsolute configuration: (S)
(S)-1-(5-Bromofuran-2-yl)ethanolC6H7BrO2[α]D25=-20.1 (c 1.0, CHCl3)ee = 95% on Chrompack CP-Chirasil-DEX CB GC columnSource of chirality: enzymatic resolutionAbsolute configuration: (S)
(S)-1-(5-(2-Chlorophenyl)furan-2-yl)ethanolC12H11ClO2[α]D25=-1.6 (c 1.0, CHCl3)ee = 98% on Chrompack CP-Chirasil-DEX CB GC columnSource of chirality: enzymatic resolutionAbsolute configuration: (S)
(S)-1-(5-(4-Bromophenyl)furan-2-yl)ethanolC12H11BrO2[α]D25=+5 (c 1.0, CHCl3)ee = 91% on Chrompack CP-Chirasil-DEX CB GC columnSource of chirality: enzymatic resolutionAbsolute configuration: (S)
(S)-1-(5-(4-Nitrophenyl)furan-2-yl)ethanolC12H11NO4[α]D25=+2.3 (c 1.0, CHCl3)ee = 89% on Chrompack CP-Chirasil-DEX CB GC columnSource of chirality: enzymatic resolutionAbsolute configuration: (S)
(S)-1-(5-(2-Methyl-4-nitrophenyl)furan-2-yl)ethanolC13H13NO4[α]D25=-2.3 (c 1.0, CHCl3)ee = 95% on Chrompack CP-Chirasil-DEX CB GC columnSource of chirality: enzymatic resolutionAbsolute configuration: (S)
Ethyl 4-(5-((S)-1-hydroxyethyl)furan-2-yl)benzoateC15H16O4[α]D25=+5.8 (c 1.0, CHCl3)ee = 93% on Chrompack CP-Chirasil-DEX CB GC columnSource of chirality: enzymatic resolutionAbsolute configuration: (S)
