| 摘要 |
<p>PURPOSE:To prepare p-chloroxylenol useful as a synthetic intermediate for fungicides, pesticides, etc., economically, in high yield, by chlorinating xylenol using a hydrochloric acid solution and a hydrogen peroxide solution as chlorinating agents. CONSTITUTION:Chlorinated xylenol is prepared by adding 5-60% hydrogen peroxide solution to a solution containing xylenol and 5-38% hydrochloric acid solution using a catalyst comprising a metal chloride such as aluminum chloride, anhydrous ferric chloride, etc. The produced chlorinated xylenol is separated by filtration, and the filtrate is recycled to the reaction system. Use of a chlorinated hydrocarbon such as carbon tetrachloride or perchloroethylene as the solvent of the above solution not only improves the activity of the catalyst and lowers the reaction temperature but also enables the filtration and separation of the p-chloroxylenol in high purity because the p-chlorophenol is exclusively precipitated as the first precipitate owing to the solubility different of the organic materials to the solvent.</p> |
