title: Enantioselective syntheses and sensory properties of 2-methyl-tetrahydrofuran-3-thiol acetates.
abstract: The enantioselective synthesis of four stereoisomers of 2-methyl-tetrahydrofuran-3-thiol acetate was achieved. The two enantiomers of the important intermediate cis-2-methyl-3-hydroxy-tetrahydrofuran were obtained by Sharpless asymmetric dihydroxylation (AD), whereas the two enantiomers of trans-2-methyl-3-hydroxy-tetrahydrofuran were derived from the corresponding optically active cis-isomers by Mitsunobu reaction. Each stereoisomer of 2-methyl-3-hydroxy-tetrahydrofuran went through mesylation and nucleophilic substitution to afford the corresponding product with specific configuration. (2R,3S)- and (2R,3R)-2-methyl-tetrahydrofuran-3-thiol acetate were obtained in 80% ee, whereas the (2S,3R)- and (2S,3S)-isomers were in 62% ee. The odor properties of the synthesized four stereoisomers were evaluated by gas chromatography-olfactometry (GC-O), which revealed perceptible differences among stereoisomers both in odor features and in intensities.
authors.affiliation: School of Food Chemistry, Beijing Key Laboratory of Flavor Chemistry, Beijing Technology and Business University , Beijing 100048, China.
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Dai
authors.forename: Junqiang
authors.initials: J
authors.lastname: Shao
authors.forename: Shaoxiang
authors.initials: S
authors.lastname: Yang
authors.forename: Baoguo
authors.initials: B
authors.lastname: Sun
authors.forename: Yongguo
authors.initials: Y
authors.lastname: Liu
authors.forename: Ting
authors.initials: T
authors.lastname: Ning
authors.forename: Hongyu
authors.initials: H
authors.lastname: Tian
mesh_terms: D000085:Acetates / Q000737:chemistry*; D000328:Adult; D005260:Female; D005421:Flavoring Agents / Q000138:chemical synthesis* / Q000737:chemistry; D005663:Furans / Q000737:chemistry*; D006801:Humans; D008297:Male; D009812:Odorants / Q000032:analysis; D013237:Stereoisomerism; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013649:Taste; D055815:Young Adult
chemical_list: D000085:Acetates; D005421:Flavoring Agents; D005663:Furans; D013438:Sulfhydryl Compounds; C550584:2-methyltetrahydrofuran
keywords: 2-methyl-tetrahydrofuran-3-thiol acetate; GC−O; Mitsunobu reaction; Sharpless AD; enantioselective synthesis; sensory properties