Synthesis of Benz[<i>d</i>]oxazolones Involving Concomitant Acetyl Migration from Oxygen to Nitrogen
作者:Sibdas Ray、Sukla Ghosh
DOI:10.1080/00397910903245158
日期:2010.7.27
Heating of o-acetoxybenzoyl azides 6–10 in toluene leads to the Curtius reaction, which, when followed by closure of oxazolone ring with concomitant migration of acetyl group from oxygen to nitrogen, produces 3-acetoxybenz[d]oxazol-2(3H)-ones 11–15, which undergo hydrolysis with hot dilute hydrochloric acid to furnish benz[d]oxazol-2(3H)-ones 17–21. Thermal reaction of 2-hydroxy-5-nitrobenzoyl azide
在甲苯中加热邻乙酰氧基苯甲酰叠氮化物 6-10 导致 Curtius 反应,随后恶唑酮环闭合,同时乙酰基从氧迁移到氮,生成 3-乙酰氧基苯并[d]恶唑-2(3H) -ones 11-15,用热的稀盐酸水解,得到苯并[d]恶唑-2(3H)-ones 17-21。2-羟基-5-硝基苯甲酰叠氮化物 (22) 在甲苯中的热反应最终产生 5-硝基苯并[d]恶唑-2(3H)-酮 (20) 和 5-硝基苯并[d]异恶唑-3(2H)的混合物)-一 (23)。