dl-萘普生重排合成的工艺研究V~Δ

SYNTHESIS OF dl NAPROXEN BY 1,2 ARYL REARRANGEMENT.V

以２－甲氧基萘为起始原料，经二溴化、脱溴、偶联、缩酮化、重排、水解得ｄｌ－萘普生（１），以２－甲氧基萘计算，总收率为７７％。

Methoxynaphthalene was subjected to bromination and debromination in one pot reaction to afford 2 bromo 6 methoxynaphthalene(3)while 5 bromo substituent of 2 was selectively removed by AlCl 3/CH 3NO 2 system.In the presence of a catalytic amount of Fe(acac) 3,the coupling reaction of 6 methoxy 2 naphthylmagnesium bromide with 2 bromopropionyl chloride provided 2 bromo 1 (6 methoxy 2 naphthyl)propan 1 one(4),which was converted to dl naproxen by ketalization,rearrangement,saponification and acidification.The overall yield was 77% from 2 methoxynaphthalene.