Method used for preparing o-nitrobenzyl bromide

The invention discloses a novel preparation method of o-nitrobenzyl bromide. According to the preparation method, ortho-nitrotoluene is taken as a raw material, azodiisobutyronitrile is taken as a catalyst, at 20 to 100 DEG C, a bromination reagent is adopted for bromination to prepare the target product. Compared with the prior art, the preparation method possesses following advantages: 1, yieldis increased obviously from about 60% to about 90%; 2, the bromination reagent can be recycled, and bromine element utilization rate is relatively high, is 90% or higher; 3, reactants can be subjectedto direct mixing reaction, so that operation complexity is reduced; and 4, reaction conditions are convenient to control, the post-treatment is simple, less three waste is generated, and the industrial using value is relatively high. 本发明公开了种新的邻硝基苄溴的制备方法：以邻硝基甲苯为原料、偶氮二异丁腈为催化剂，在20-100℃下用种溴代试剂经溴化制备目标产物。与现有技术相比，本发明具有以下优点：1.收率显著提高，由60％左右提高到90％左右；2.溴代试剂可循环再利用，溴元素的利用率较高，可达90％以上；3.反应物可以直接混合反应，减少了操作的复杂性；4.反应条件易控制，后处理简单，三废产生量少，有较大的工