| 摘要 |
PURPOSE:In reacting an aniline with an ethylene glycol in the presence of a catalyst in a gaseous phase, to obtain an indole useful as a raw material for synthesizing especially perfume or an amino acid, by circulating a noncondensing reaction gas to the reaction system. CONSTITUTION:An aniline such as aniline is reacted with the ethylene glycol 1 such as ethylene glycol preferably together with hydrogen 2 in the presence of a solid acid catalyst or a metal catalyst preferably at 250-500 deg.C in a gaseous phase in the reaction system 4 to give the gaseous reaction mixture 5, which is condensed 6 conventionally. In the operation, the prepared noncondensing reaction gas 8 is circulated 3 to the reaction system 4 and used as a diluent for the raw material 1, so that the yield of the indole is improved and the reduction in catalytic activity is suppressed. |
