Palladium-catalyzed highly regioselective 2-arylation of 2,x-dibromopyridines and its application in the efficient synthesis of a 17β-HSD1 inhibitor
作者:Qizhong Zhou、Bin Zhang、Liangjun Su、Tiansheng Jiang、Rener Chen、Tieqi Du、Yuyuan Ye、Jianfen Shen、Guoliang Dai、Deman Han、Huajiang Jiang
DOI:10.1016/j.tet.2013.10.065
日期:2013.12
2,3- and 2,5-Dibromopyridines reacted with arylboronic acids, catalyzed by Pd(OAc)(2)/PPh3 in the presence of K2CO3 in CH3CN/MeOH (2:1) at 50 degrees C for 24 h, to afford 2-aiylpyridines in good to high yields, while 2,4-dibromopyridine reacted with arylboronic acid pinacol esters, catalyzed by Pd(OAc)(2)/PPh3 in the presence of KOH in CH3CN at 70 degrees C for 24 h, to afford 2-arylpyridines in good to high yields. To expand this methodology, a 170-HSD1 inhibitor was synthesized in good yield. (C) 2013 Elsevier Ltd. All rights reserved.