Abstract 3-Indolylalkanoic acids 2 react with benzoic acid anhydride under catalysis of Et 2 O-ZnCl 2 and mild conditions to furnish the 1-phenyl-substituted pyrano [3, 4-b] indol-3-ones 1c, 1d, and 3a, 3b. Products 1c, 1d, and 3b may be converted into the novel functionalized carbazoles 4 and 5 by reaction with acceptor-substituted alkynes.