Preparation of 5-Brominated and 5,5‘-Dibrominated 2,2‘-Bipyridines and 2,2‘-Bipyrimidines
作者:Peter F. H. Schwab、Frank Fleischer、Josef Michl
DOI:10.1021/jo010707j
日期:2002.1.1
two reactive positions with lithium di-tert-butyl-(2,2,6,6-tetramethylpiperidino)zincate. 5,5'-Dibromo-2,2'-bipyridine was obtained by the reductive symmetric coupling of 2,5-dibromopyridine with hexa-n-butyldistannane. The yields of these coupling reactions ranged from 70 to 90%. 5-Bromo- and 5,5'-dibromo-2,2'-bipyrimidines were obtained in yields of 30 and 15%, respectively, by bromination of 2,2'-bipyrimidine
已经开发了可用于制备金属络合物分子棒的5-溴和5,5'-二溴的2,2'-联吡啶和2,2'-联嘧啶的有效合成方法。通过以下方法获得了5-溴-2,2'-联吡啶,5-溴-5'-正丁基-2,2'-联吡啶和5-溴-5'-正己基-2,2'-联吡啶2,5-二溴吡啶与2-三甲基苯乙烯基吡啶或必要的5-烷基-2-三甲基苯乙烯基吡啶的斯蒂勒偶联,是通过3-烷基吡啶.BF(3)络合物的区域选择性锌化而获得的,该络合物在较少受两个反应位置影响的情况下与二锂-叔丁基-(2,2,6,6-四甲基哌啶子基)锌酸酯。通过5,5′-二溴-2,2′-联吡啶通过2,5-二溴吡啶与六正丁基二锡烷的还原对称偶联而获得。这些偶联反应的产率为70-90%。