W. E. Noland, J. E. Johnson, “3-(3-Indolyl)phthalides and 3-(2-Carboxy-benzyl)indoles,” J. Am. Chem. Soc. Vol. 82, No. 19, 1960, pp. 5143-5147.

has been cited by the following article:

• TITLE: TsOH·H2O-Catalyzed Friedel-Crafts of Indoles of 3-Hydroxyisobenzofuran-1(3H)-One with Indoles: Highly Synthesis of 3-Indolyl-Substituted Phthalides

  AUTHORS: Hongying Tang, Xinyu Zhang, Airu Song, Zhongbiao Zhang

  KEYWORDS: Synthesis; 3-Indolyl-Substituted Phthalides; Friedel-Crafts Alkylation; 3-Hydroxyisobenzofuran-1(3H)-One; Indole

  JOURNAL NAME: Modern Research in Catalysis, Vol.1 No.2, July 24, 2012

  ABSTRACT: An efficient and facile method for the synthesis of 3-indolyl-substituted phthalides by Friedel-Crafts alkylation of indoles with 3-hydroxyisobenzofuran-1(3H)-one has been developed. Using only 2 mol-% TsOH·H2O as the catalyst, various substituted indoles can react smoothly at room temperature to give the corresponding phthalides products in good to excellent yields (up to 96%).