2-氰基-2,2-二(4-溴苄基)乙酸乙酯的合成

Synthesis of 2-Cyano-2,2-bis(4-bromobenzyl) ethyl Acetate

室温下,在二氯甲烷溶剂中,用三溴化硼溴化4-溴甲苯甲基侧链,合成了4-溴溴苄,收率84.4%;无水乙醇回流条件下,物料比n(4-溴溴苄)∶n(吡啶)=1∶1时,合成溴化N-(4-溴苄基)吡啶,收率95.3%;物料比n(溴化N-(4-溴苄基)吡啶)∶n(丙二腈)=2∶1时,合成2,2-二(4-溴苄基)丙二腈,收率67.0%;二氯亚砜催化2,2-二(4-溴苄基)丙二腈在有水的条件下醇解合成2-氰基-2,2-二(4-溴苄基)乙酸乙酯,收率65.3%。

A yield of 84.4% for the preparation of 4-bromobenzyl bromide was achieved using 4-bromotoluene as the raw material and boron tribromide as the brominating agent at room temperature. A N-（4-bromobenzyl） pyridine yield of 95.3%was obtained when the ratio of 4-bromobenzyl bromide/pyridine equal to 1 ： 1 under anhydrous ethanol refluxing. Then, N-（4-bromobenzyl） pyridine was reacted with malononitrile to give 2,2-bis （4-bromobenzyl） malononitrile, and a yield of 67.0% was obtained at N-（4-bromobenzyl） pyridine/malononitrile ratio of 2 ： 1. At the presence of water and thionyl chloride as the catalyst, a yield of 65.3% for 2-cyano-2,2-bis （4-bromobenzyl） ethyl acetate was achieved from alcoholization reaction of 2,2-bis（4-bromobenzyl） malononitrile.