6-甲氧基-2-(4-甲氧苯基)苯并[b]噻吩及其异构体的合成研究

目的 合成盐酸雷洛昔芬关键中间体6-甲氧基-2-(4-甲氧苯基)苯并Lb]噻吩。方法 以4-甲氧基苯乙酮为原料，经溴代、硫醚化先制得α-(3—甲氧苯硫基)-4-甲氧基苯乙酮，再在多聚磷酸(PPA)的催化下，经环合及重排制得目标产物。结果 与结论从目标产物母液中分离得到3个异构体，它们的化学结构根据高分辨质谱、核磁共振氢谱与红外光谱测试数据确认。改用甲硝酸为催化剂，可提高目标产物的收率。

Studies on the synthesis of 6-methoxy-2-(4-methoxyphenyl)benzo[b]thiophene and its isomers

Aim To synthesize 6-methoxy-2-(4-methoxyphenyl)benzothiophene which is an important intermediate for synthesis of raloxifene hydrochloride.Method The target compound was synthesized through bromination and thioetherification from 4-methoxyacetophenone as a starting material.Then polyphosphoric acid(PPA) was used as a catalyst for the cyclization-rearrangement reaction.Results and Conclusion Three isomers accompanied by the target compound were isolated from the mother liquor and their chemical structures were confirmed by IR, 1H-NMR and HRMS.After using methanesulfonic acid as a catalyst instead of PPA,the yield of the target compound was increased in this improved synthesis.