title: Synthesis of benzofused five-ring sultams via Rh-catalyzed C-H olefination directed by an N-Ac-substituted sulfonamide group.
abstract: A Rh-catalyzed N-Ac-sulfonamide group directed C-H olefination-cyclization to afford benzofused five-ring sultam is described with high yield and a wide range of substrate scope. The N-acetyl group is a key for this transformation implying that N-H acidity is the major influence. The acetyl group is removed under mild conditions in excellent yield to provide NH-free sultam that can be transformed into various benzofused five-ring sultam analogues via acylation, nucleophilic substitution, and Mitsunobu alkylation.
authors.affiliation: College of Chemistry and Chemical Engineering, Harbin Normal University , Harbin 150025, PR China.
authors.forename: Xueyuan
authors.initials: X
authors.lastname: Li
authors.forename: Yi
authors.initials: Y
authors.lastname: Dong
authors.forename: Fengyu
authors.initials: F
authors.lastname: Qu
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
mesh_terms: D002384:Catalysis; D003500:Cyclization; D006860:Hydrogen Bonding; D015394:Molecular Structure; D009282:Naphthalenesulfonates / Q000138:chemical synthesis* / Q000737:chemistry*; D012238:Rhodium / Q000737:chemistry*; D013237:Stereoisomerism; D013449:Sulfonamides / Q000138:chemical synthesis
chemical_list: D009282:Naphthalenesulfonates; D013449:Sulfonamides; C016768:naphthosultone; D012238:Rhodium