Solar photo-thermochemical syntheses of 4-bromo-2,5-substituted oxazoles from N-arylethylamides
作者:Milan Dinda、Supravat Samanta、Suresh Eringathodi、Pushpito K. Ghosh
DOI:10.1039/c3ra47603k
日期:——
isolated yields were in the range 42–82%. Benzylic bromination, followed by O–C bond formation through intramolecular nucleophilic substitution, and a second benzylic bromination followed by HBr elimination, gave the oxazole ring. A third bromination of the ring yielded the final product. The feasibility of synthesizing thiazole derivatives using a similar approach was also demonstrated. During the course
最近报道了在专门设计的反应器中有效进行的太阳能光热化学C(sp 3)-H溴化反应。在本研究中,使用此方法可以更复杂地由N-芳基乙酰胺形成4-溴-2,5-取代的恶唑。一锅合成用N进行晴天,在6个小时(上午10.00到下午4.00)中使用-溴代琥珀酰亚胺-二氯乙烷。孤立的产率在42%至82%之间。苯甲基溴化,然后通过分子内亲核取代形成OC键,然后再进行苄基溴化,再通过HBr消除,得到恶唑环。环的第三次溴化反应产生最终产物。还证明了使用类似方法合成噻唑衍生物的可行性。在反应过程中,琥珀酰亚胺和HBr在水相中共生成。冷却后,用NaBrO 3和另外的酸处理返回试剂,分离出的产率为57%。结果,整体方法更加绿色。