title: 3-Alkyl-3-(alkylamino)indolin-2-ones via Base-Mediated C-Arylation of 2-Nitrobenzenesulfonamides.
abstract: Resin-bound intermediates prepared from polymer-supported amino acid esters, 2-nitrobenezenesulfonyl chlorides, and alcohols were used to synthesize 3-alkyl-3-(alkylamino) indolin-2-ones. The key step of the reaction sequence was the formation of a quaternary carbon via the base-mediated C-arylation of 2-nitrobenzenesulfonamides. The cleavage of the acyclic precursors from the resin and subsequent reduction of the nitro group by Zn in acetic acid triggered the spontaneous cyclization of the arylated compounds to indolinones. The synthesis was carried out using simple commercially available building blocks under mild conditions and provided the 3,3-disubstituted indolinone derivatives with good overall yields however, the arylation reaction resulted in the epimerization of the quaternary carbon.
authors.affiliation: †Department of Organic Chemistry, Institute of Molecular and Translational Medicine, Faculty of Science, Palacky University, 17. listopadu 12, 771 46 Olomouc, Czech Republic.
authors.forename: Vanesa
authors.initials: V
authors.lastname: Giménez-Navarro
authors.affiliation: †Department of Organic Chemistry, Institute of Molecular and Translational Medicine, Faculty of Science, Palacky University, 17. listopadu 12, 771 46 Olomouc, Czech Republic.
authors.forename: Tereza
authors.initials: T
authors.lastname: Volná
authors.affiliation: †Department of Organic Chemistry, Institute of Molecular and Translational Medicine, Faculty of Science, Palacky University, 17. listopadu 12, 771 46 Olomouc, Czech Republic.|‡Department of Chemistry and Biochemistry, University of Notre Dame, 251 Nieuwland Science Center, Notre Dame, Indiana 46556, United States.
authors.forename: Viktor
authors.initials: V
authors.lastname: Krchňák
mesh_terms: D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013449:Sulfonamides / Q000737:chemistry*
chemical_list: D007211:Indoles; D013449:Sulfonamides; C456900:indolin-2-one
keywords: C−C bond formation; arylation; heterocycle; nitrobenzenesulfonamides; oxindole; quaternary carbon; solid-phase synthesis