| 摘要 |
PURPOSE:To prepare the titled compound useful as an intermediate of an insecticide (carbofuran), economically, in one step, by reacting catechol with a specific aldehyde or alcohol in the presence of a solid acid catalyst in vapor phase. CONSTITUTION:Catechol is made to react with the aldehyde or alcohol of formula I -II (R and R' are lower alkyl or H) in the presence of a solid acid catalyst such as silica, alumina, magnesia, boria, silica-alumina, silica-magnesia, alumina-boria, alumina phosphate, boria phosphate, acid clay, diatomaceous earth, etc., in vapor phase, preferably at 200-300 deg.C, especially 220-260 deg.C. The compound of formula III can be prepared by this process economically, without using a solvent. The weight ratio of catechol to the compound of formula I or IIis preferably 1 to 1-5. The catalyst may contain a noble metal such as palladium, platinum, etc. supported on the carrier in an amount of 0.1-1wt%. |
