Synthesis of a Sodium–Hydrogen Exchange Type 1 Inhibitor: An Efficient Cu-Catalyzed Conjugated Addition of a Grignard Reagent to an Acetyl Pyridinium Salt
作者:Wenjun Tang、Nitinchandra D. Patel、Xudong Wei、Denis Byrne、Ashish Chitroda、Bikshandarkoil Narayanan、Alexander Sienkiewicz、Laurence J. Nummy、Max Sarvestani、Shengli Ma、Nelu Grinberg、Heewon Lee、Soojin Kim、Zhibin Li、Earl Spinelli、Bing-Shiou Yang、Nathan Yee、Chris H. Senanayake
DOI:10.1021/op300331b
日期:2013.3.15
facile and economical five-step process for the synthesis of a sodium–hydrogen exchange type I inhibitor (NHE-1) was developed from readily available starting materials in 43% overall yield. Key transformations included a highly efficient copper-catalyzed conjugate addition of 2-trifluoromethylphenyl Grignard reagents to acetyl pyridinium salts, a facile hydrogenation of 4-aryl dihydropyridines, a regioselective
从容易获得的起始原料开发了一种简便,经济的五步法合成钠-氢交换I型抑制剂(NHE-1),总产率为43%。关键的转变包括将2-三氟甲基苯基格氏试剂高效铜催化共轭加成到乙酰基吡啶鎓盐中,4-芳基二氢吡啶的便捷氢化,区域选择性芳族溴化,钯的芳基溴化物羰基化高效反应以及高-产生酰基胍的形成。开发了一种安全且可扩展的制备2-三氟甲基苯基格氏试剂的方案,并提出了一种用N-乙酰基-L控制钯含量的简便方法-半胱氨酸作为清除剂被证明。还解决了在酰基胍形成过程中控制关键的二酰化副产物形成的过程问题。