Studies on the syntheses of heterocyclic compounds. Part 865. A novel synthesis of indole derivatives by intramolecular nucleophilic aromatic substitution
Cyclisation of N-(2-bromo-4,5-dimethoxyphenethyl)acetamide (6) afforded 1-acetyl-2,3-dihydro-5,6-dimethoxy-1H-indole (13) by intramolecular nucleophilic aromatic substitution using sodium hydride and cuprous halide in dimethylformamide. The dihydroindoles (14), (15), and (16) were also synthesised from the corresponding amides (8) and (10) and the carbamate (12) in a similar manner. The dihydroindoles