Regioselective Synthesis of 2<i>H</i>-Benzopyrano[3,2-<i>c</i>]quinolin-7(8<i>H</i>)-ones by Radical Cyclization
作者:K. C. Majumdar、P. P. Mukhopadhyay
DOI:10.1055/s-2003-36268
日期:——
Different 4-hydroxyquinolin-2(1H)-ones were treated with 2-bromobenzyl bromide and 2-bromo-5-methoxybenzyl bromide in the presence of anhydrous potassium carbonate in acetone to afford a number of 4-(2'-bromobenzyloxy)quinolin-2(1H)-one derivatives in 80-85% yield. These 4-(2'-bromobenzyloxy)quinolin-2-(1H)-ones were then refluxed with tributyltin chloride and sodium cyanoborohydride in benzene under
在丙酮中,在无水碳酸钾存在下,用 2-溴苄基溴和 2-溴-5-甲氧基苄基溴处理不同的 4-羟基喹啉-2(1H)-酮,得到许多 4-(2'-溴苄氧基)喹啉-2(1H)-one 衍生物,产率为 80-85%。然后将这些 4-(2'-溴苄氧基)喹啉-2-(1H)-酮与三丁基氯化锡和氰基硼氢化钠在苯中在氮气中在催化量的 AIBN 存在下回流 4-5 小时以得到 2H -苯并吡喃[3,2-c]quinolin-7(8H)-ones,产率为 70-80%。