Reaction Steps
The indoles prepared by the above-mentioned method of the present invention include, for example, indole, 1-methylindole, 1-ethylindole, 1-phenylindole, 1-benzylindole, 3-methylindole, 4-methylindole, 5-methylindole, 6-methylindole, 7-methylindole, 1,2-dimethylindole, 1,3-dimethylindole, 1,4-dimethylindole, 1,5-dimethylindole, 1,6-dimethylindole, 1,7-dimethylindole, 3,4-dimethylindole, 3,5-dimethylindole, 3,6-dimethylindole, 3,7-dimethylindole, 1-ethyl-2-methylindole, 1-ethyl-3-methylindole, 1-ethyl-4-methylindole, 1-ethyl-5-methylindole, 1-ethyl-6-methylindole, 1-ethyl-7-methylindole, 1,3-diethylindole, 1,3,7-trimethylindole, 1,3,4-trimethylindole, 1,3,5-trimethylindole, 1,3,6-trimethylindole, 1,2,5-trimethylindole, 1-ethyl-2,5-dimethylindole, 1-ethyl-3,5-dimethylindole, 1-ethyl-3,6-dimethylindole, 1-ethyl-3,7-dimethylindole, 1-benzyl-3-methylindole, 1-methyl-5-methoxyindole, 1,3-dimethyl-5-methoxyindole, 1-benzyl-5-methoxyindole and the like. Concomitantly, two kinds of indoles may be obtained depending on the starting compounds used. For example, 1,3-dimethylindole and 1,2-dimethylindole are obtained by using N-methylaniline and propylene glycol (or propylene (oxide) as the starting compounds. On the other hand, 4-methylindole and 6-methylindole are obtained by using m-toluidine and ethylene glycol as the starting compounds.
