无催化剂条件下微波合成2-羟基苯并咪唑

Synthesis of 2-Hydroxybenzimidazole under Microwave Irradiation without Catalysis

在无催化剂条件下,利用邻苯二胺与尿素的熔融缩合反应,微波辐射合成了2-羟基苯并咪唑,即苯并咪唑酮。合成无需溶剂和催化剂,反应速度快,操作简便、安全,过程节能、环保。对影响合成收率的条件因素进行了考察。结果表明:微波输出功率为638W、间歇辐射时间9min、n(邻苯二胺)∶n(尿素)=1∶1时,收率可达88.4%,产品经红外光谱确认。

2-Hydrxybenzimidazole was synthesized via the condensation reaction of o-phenylenediamine and urea under microwave irradiation without catalysis condition. The methods had a characteristic of fast reaction, simple operation, safety, low energy consumptions and environmental protection. The optimum conditions were as follow： microwave power 638 W, microwave irradiation time 9 min, the mole ratio of o-phenylendiamin and urea 1：1.1. Under the above conditions, the yield was 88.4%. The product was identified by IR.