title: Organocatalytic asymmetric Friedel-Crafts reaction of sesamol with isatins: access to biologically relevant 3-aryl-3-hydroxy-2-oxindoles.
abstract: The Friedel-Crafts reaction of electron-rich phenols with isatins was developed by employing bifunctional thiourea-tertiary amine organocatalysts. Cinchona alkaloid derived thiourea epiCDT-3 a efficiently catalyzed the Friedel-Crafts-type addition of phenols to isatin derivatives to provide 3-aryl-3-hydroxy-2-oxindoles 7 and 9 in good yield (80-95 %) with good enantiomeric excess (83-94 %). Friedel-Crafts adduct 7 t was subjected to a copper(I)-catalyzed azide-alkyne cycloaddition to obtain biologically important 3-aryl-3-hydroxy-2-oxindole 11 in good enantiomeric excess and having a 1,2,3-triazole moiety.
authors.affiliation: Department of Chemistry, U.G.C. Centre of Advance Studies in Chemistry, Guru Nanak Dev University, Amritsar (India), Fax: (+91) 183-2258820.
authors.forename: Akshay
authors.initials: A
authors.lastname: Kumar
authors.forename: Jasneet
authors.initials: J
authors.lastname: Kaur
authors.forename: Pankaj
authors.initials: P
authors.lastname: Chauhan
authors.forename: Swapandeep Singh
authors.initials: SS
authors.lastname: Chimni
mesh_terms: D052117:Benzodioxoles / Q000737:chemistry*; D002384:Catalysis; D002930:Cinchona Alkaloids / Q000737:chemistry; D007211:Indoles / Q000138:chemical synthesis*; D007510:Isatin / Q000031:analogs & derivatives* / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry*; D013890:Thiourea / Q000737:chemistry
chemical_list: D052117:Benzodioxoles; D002930:Cinchona Alkaloids; D007211:Indoles; D010636:Phenols; D007510:Isatin; C025583:sesamol; D013890:Thiourea
keywords: alkaloids; alkylation; click chemistry; organocatalysis; sesamol