2-卤乙基-2-(6’-甲氧基-2’-萘基)-4-甲基-1,3-二氧杂环戊烷重排合成外消旋体萘普生

Synthesis of dl-Naproxen via Rearrangement of 2-Haloethyl-2-(6’-methoxy-2’-naphthyl)-4-methyl-1,3-dioxolane

以溴化铜或氯化铜为卤化剂 ,6-甲氧基 -2 -丙酰基萘经羰基 α-卤化、1 ,2 -丙二醇缩酮化、醋酸锌或氧化锌催化重排和水解等反应合成外消旋体萘普生 ,总收率为 85 %～ 90 .4% (以 6-甲氧基 -2 -丙酰基萘计 ) .“一锅法”重排合成外消旋体萘普生 ,不需分离中间体 ,操作简便、收率高 .以氯化铜为卤化剂。

Methoxy 2 propionyl naphthalene was halogenated with cupric halide, then ketalated with 1,2 propanediol, catalytically rearranged by Zn(OAc) 2 or ZnO to give dl naproxen in yield of 85%~90 4% based on 6 methoxy 2 propionyl naphthalene. All reactions were carried out in 'one pot' without additional separation of the intermediates. The route of catalytic rearrangement by using cupric chloride as halogenating agent and zine oxide as catalyst via 2 chloro 2 (6 methoxy 2 naphthyl) 4 methy 1,3 dioxolane appeared more economical due to the cheapness of reagents and simplicity in separation.