| 摘要 |
<p>A novel, simple, high-yield process for the production of 2,3,5,6-tetrachloropyridine comprises reacting an ester of 2,2,4-trichloro-4-cyanobutyric acid with excess phosphorus oxychloride in the presence of a catalytic amount of hydrogen chloride and optionally in the presence of an aprotic inert solvent, at a temperature of 100-160 DEG C, preferably at 120-140 DEG C for about 5-10 hours, under elevated pressure, if necessary.</p> |
