Synthesis of nitro- and aminoindoles
Optimal conditions are proposed for the direct nitration of 2,3-dimethylindoles containing methyl and methoxy groups in the benzene ring. In contrast to 5- and 6-methylindoles and 5- and 6-methoxyindoles, nitration of 7-methyl-and 7-methoxy-2,3-dimethylindoles proceeds differently under the same conditions. A series of previously unreported aminoindoles was obtained by reduction of the nitroindoles.