| 摘要 |
PURPOSE:To industrially and advantageously obtain the titled compound useful as an intermediate for agricultural chemicals, etc., by reacting isobutylene and/or tertiary butyl alcohol with isobutyl aldehyde in the vapor phase in the presence of a solid catalyst at a specific temperature. CONSTITUTION:Isobutylene and/or tertiary butyl alcohol and isobutyl aldehyde are reacted in the presence of a solid acid catalyst, e.g. silica alumina, acid clay, synthetic zeolite, niobic acid, etc., having acid points with >=-5.6 maximum acid strength expressed in terms of Ho function value, particularly niobic acid catalyst under condition of 150-350 deg.C temperature and preferably further pressurized condition to afford the aimed 2,5-dimethyl-2,4-hexadiene useful as an intermediate for insecticides, medicines or various organic syntheses in addition to the above-mentioned agricultural chemicals in good yield. Higher activity and selectivity for the aimed compound are obtained by using a catalyst prepared by treating the niobic acid with a mineral acid, particularly sulfuric acid or phosphoric acid. |
