Facile synthesis of 3-aryloxindoles via brønsted acid catalyzed Friedel-Crafts alkylation of electron-rich arenes with 3-diazooxindoles.
A simple metal-free method for the synthesis of 3-aryloxindoles via Brønsted acid catalyzed aromatic C-H functionalization of electron-rich arenes with 3-diazooxindoles is developed. In the presence of a catalytic amount of TfOH, a series of 3-aryloxindoles are synthesized as single regioisomers in good to excellent yields. This transformation is proposed to proceed through acid-catalyzed protonation of 3-diazooxindoles into diazonium ions followed by Friedel-Crafts-type alkylation of arenes.
Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, and Department of Chemistry, East China Normal University , 3663 North Zhongshan Road, Shanghai 200062, China.
Changwei
C
Zhai
Dong
D
Xing
Changcheng
C
Jing
Jun
J
Zhou
Chengjin
C
Wang
Dongwei
D
Wang
Wenhao
W
Hu
D000143:Acids / Q000737:chemistry*; D000478:Alkylation; D001391:Azo Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D002384:Catalysis; D003979:Diazonium Compounds / Q000737:chemistry; D004583:Electrons; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure
D000143:Acids; D001391:Azo Compounds; D003979:Diazonium Compounds; D007211:Indoles