title: Thia-prins bicyclization approach for the stereoselective synthesis of dithia- and azathia-bicycles.
abstract: A novel thia-Prins bicyclization approach has been developed for the first time for the synthesis of hexahydro-2H-thieno[3,2-c]thiopyran derivatives from the coupling of homoallylic mercaptans such as hex-3-ene-1,6-dithiol with various aldehydes using 10 mol % InBr3 in dichloromethane with high selectivity. In addition, the coupling of (E)-N-(6-mercaptohex-3-enyl)-4-methylbenzenesulfonamide with aldedydes affords the corresponding N-tosyloctahydrothiopyrano[4,3-b]pyrrole derivatives in good yields. This reaction is a stereoselective affording trans-fused product from E-homoallyllic mercaptan and cis-fused product from Z-homoallyllic mercaptan.
authors.affiliation: Natural Product Chemistry, ‡Centre for Nuclear Magnetic Resonance, §Laboratory of X-ray Crystallography, Indian Institute of Chemical Technology , Hyderabad 500 007, India.
authors.forename: B V Subba
authors.initials: BV
authors.lastname: Reddy
authors.forename: A
authors.initials: A
authors.lastname: Venkateswarlu
authors.forename: Prashant
authors.initials: P
authors.lastname: Borkar
authors.forename: J S
authors.initials: JS
authors.lastname: Yadav
authors.forename: M
authors.initials: M
authors.lastname: Kanakaraju
authors.forename: A C
authors.initials: AC
authors.lastname: Kunwar
authors.forename: B
authors.initials: B
authors.lastname: Sridhar
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D007204:Indium / Q000737:chemistry; D015394:Molecular Structure; D011714:Pyrans / Q000138:chemical synthesis*; D011758:Pyrroles / Q000138:chemical synthesis*; D013237:Stereoisomerism; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013449:Sulfonamides / Q000737:chemistry*; D014050:Toluene / Q000031:analogs & derivatives* / Q000737:chemistry; D000096926:Benzenesulfonamides
chemical_list: D000447:Aldehydes; D007204:Indium; D011714:Pyrans; D011758:Pyrroles; D013438:Sulfhydryl Compounds; D013449:Sulfonamides; D014050:Toluene; C530781:indium bromide; C522033:thiopyran; C025417:4-toluenesulfonamide; D000096926:Benzenesulfonamides