A novel method for the synthesis of boscalid,in which Pd( OH) 2/C promoted the Suzuki reaction of p-chlroro-phenyl bo-ronic acid and o-nitro-bromobenzene,after the reduction of 2-(4-chlorophenyl)nitrobenzene with hydrazine,coupling with 2-chloro-nicotinyl chloride to obtain product was reported. The influences of reaction temperature,inorganic base,quaternary ammonium salt and solvent on the Suzuki reaction were investigated. Considering of the efficiency of reaction and cost of production,the best reac-tion condition was K3PO4·7H2O as inorganic base,tetrabutyl ammonium bromide(TBAB)as additives,and at 120℃ to react for 10 h,under this condition of Pd(OH)2/C could promoted the Suzuki reaction fulfilled. Under the same reaction condition,the recycling of Pd(OH)2/C was investigated,after recycle 6 times,the catalytic activity of Pd(OH)2/C was no obvious decreasing. The 2-(4-chlorophenyl)nitrobenzene was reduced by hydrazine in the presence of FeCl3·6H2O and active charcoal and then coupled with 2-chloro-nicotinic acid to obtain boscalid in good yield.%本文报道一种啶酰菌胺的新方法,即用Pd( OH)2/C催化的对氯苯硼酸与2-硝基溴苯的Suzuki反应、其产物2-(4-氯苯基)硝基苯经水合肼-三氯化铁体系还原后与2-氯烟酰氯或2-氯烟酸缩合得目标产物。在Su-zuki反应中,考察了反应温度、无机碱、季铵盐和溶剂对反应的影响后。再考虑到生产效率与生产成本的因素,发现以K3PO4·7H2O为无机碱,四丁基溴化铵(TBAB)为助剂,在DMF中,120℃下反应13h,Pd(OH)2/C能很好地催化对氯苯硼酸与2-硝基溴苯的Suzuki反应,并在这一的条件下考察Pd(OH)2/C循环利用的情况。
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