One-Pot Synthesis of 3-Substituted 3,4-Dihydro-1,2,3-benzotriazine Derivatives Based on the Reaction of<i>o</i>-Bromobenzyl Azides with Butyllithium
作者:Kazuhiro Kobayashi、Yuuki Chikazawa
DOI:10.1002/hlca.201500234
日期:2016.1
An efficient one‐pot procedure for the preparation of 3‐substituted 3,4‐dihydro‐1,2,3‐benzotriazines 2, 3, and 4 from o‐bromobenzyl azides 1 is described. The reaction of these azides with BuLi in THF at −78° generates o‐lithiobenzyl azides via the Br/Li exchange. These lithium compounds immediately undergo intramolecular cyclization to give the corresponding (dihydro‐1,2,3‐benzotriazinyl)lithium intermediates
描述了一种从邻溴苄基叠氮化物1制备3取代的3,4-二氢-1,2- ,3-苯并三嗪2、3和4的有效一锅法。这些叠氮化物与BuLi在-78°的THF中反应,通过Br / Li交换生成邻-硫代苄基叠氮化物。这些锂化合物会立即经历分子内环化反应,生成相应的(二氢-1,2,3-苯并三嗪基)锂中间体,这些中间体在N(3)处被各种酰化剂或BnBr捕获,专门提供中等至所需的产物。良品率高。