磺酰三唑酮的合成及工艺研究

Synthesis of Sulfentrazone and Process Research

以2,4-二氯苯胺为原料,经NaNO2重氮化后,用SnCl2还原制得2,4-二氯苯肼,和乙醛、NaOCN环合制备4,5-二氢-3-甲基-1-（2,4-二氯苯基）-1,2,4-三唑-5（1H）酮（三唑啉酮）,在常温下和CHClF2反应制得4,5-二氢-3-甲基-1-（2,4-氯-5-氨基-苯基）4-二氟甲基-1,2,4-三唑-5（1H）酮（4-取代三唑啉酮）,再经混酸硝化、铁粉还原后得4,5-二氢-3-甲基-1-（2,4-二氯-5-氨基-苯基）-4-二氟甲基-1,2,4-三唑-5（1H）酮,最后和甲基磺酰氯反应后制得N-（2,4-二氯-5-（4-二氟甲基-4,5-二氢-3-甲基-5-氧代-1H-1,2,4-三唑-1-基）苯基）甲磺酰胺（磺酰三唑酮）,并对该工艺中关键的环合步骤进行了工艺优化,实验表明,最佳的醇类溶剂为叔丁醇,环合反应温度10～15℃时产率高,催化环合反应时使用的最佳有机质子酸为乙酸,在此条件下,环合反应的产率达到89.3％.

N - （2,4-dichloro-5- （4-（difluoromethyl） -4,5-dihydro-3-methyl-5-oxo-lH-1,2,4-triazol-l-yl） phenyl） （Sulfentrazone） was synthesized from the raw material 2,4-dichloro aniline. The process went through the steps from the raw material to the target product by： diazotization with NaNO2, reduction with SnCI2, cyclization with acetaldehyde and NaOCN, difluoromethylation with CHC1F2, nitration and reduction, and the last one sulfonylation. Among those steps, the ring formation cyclization is the key. This work studied and optimized the cyclization process. The experiments show that the cyclization product can achieve 89.3% yield at the reacting condition： t-butanol as the solvent, reaction temperature of 10m 15 ℃, and acetic acid as the catalyst.