【硝化反应】肟氧化为硝基化合物（下）
肟可以直接氧化转化成硝基化合物，还可以通过间接氧化的方法转化成硝基化合物。
将肟卤化成卤代亚硝基化合物的试剂很多，例如：氯气,1液溴,2 次氯酸,1 次氯酸叔丁酯,6NBS等.3 生成的中间体卤代亚硝基化合物被硝酸, 3臭氧,4次氯酸钠溶液,5或丁基次氯酸铵6等氧化剂氧化成卤代硝基化合物。
The conversion of oximes to α-chloronitro compounds can be carried out by a one-flask operation. For example,1-chloronitrocyclohexanone is prepared in 98% yield by treatment of cyclohexanone oxime with aqueous hypochlorous acid and by subsequent treatment with a mixture of tetra-n-butylammonium hydrogen sulfate and aqueous sodium hypochlorite. The reductive dechlorination of the α-chloronitro compounds is achieved by catalytic hydrogenolysis with 1 atm H2 over 5% Pd/C in methanol-water (4:1). The final step can be replaced by treatment with either Mg or Zn dust. 6
此外，还可以通过一锅法将肟转化成卤代硝基化合物。比如通过N,N,N,-三卤代-1,3,5-三嗪, 7 氯代过氧化酶，过氧化氢和氯化钾，或OXONE和氯化钠8。其中，OXONE 是最便捷的方法9。
Oxone (1.85 g, 3 mmol) was added to a well stirred suspension of NaCl (175 mg, 3 mmol) and wet basic alumina (6 g) in chloroform(15 mL) and the mixture heated at 45 oC for 5 min. A solution of oxime (0.6mmol) in chloroform (1.5 mL) was then added and the reaction mixture stirred until the deep blue colour disappeared (1 h). The mixture was filtered under vacuum and the solution evaporated under reduced pressure. The crude material was purified by chromatography on Al2O3 (activity III,eluent petroleum ether) affording the desired gem-chloro-nitro compound with 83% yield.9
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