【摘要】 研究了雷尼镍为催化剂加氢还原2-(5-氟-2-硝基苯氧基)乙酸甲酯(1)合成7-氟-2H-[1,4]苯并噁嗪-3(4H)-酮(2)的方法,使还原、合环一次完成。考察了反应温度、催化剂、氢气压力、时间、溶剂及回收的催化剂和溶剂对反应收率的影响,确定了合成工艺条件:反应温度70℃,反应时间4h,催化剂用量为原料质量的5%,氢气压力5MPa,溶剂甲醇用量为1000mL/mol1。产品的收率92.4%,含量98%,溶剂和催化剂循环使用4次,对收率无影响。产品结构经元素分析、红外光谱、核磁共振确证。更多还原

【Abstract】 7-Fluoro-2H-1,4-benzoxazin-3(4H)-one(2) was prepared through the reaction of hydrogenization catalyzed by Rany Nickel from methyl 2-(5-fluoro-2-nitrophenoxy) acetate(1). The effect of temperature,catalyst,pressure of H2,reaction time,solvents and reclaim of all the solution and the catalyst were investigated. The optimum process conditions were determined as following:Reaction temperature was 70℃,time 4 h,the catalyst amount 5% comparing to 1 (w/w),the hydrogen pressure 5 MPa and methanol 1 000 mL/mol(1). The yield was 92.4% and the purity was 98%,all the solution and the catalyst could be reclaimed for four times and had no bad effect on the yield and purity. The structure of 2 was comformed by elementary analysis,IR,and 1H NMR.更多还原