Department of Chemistry, National Tsing Hua University , Hsinchu, Taiwan, ROC.
J Org Chem. 2014 May 16;79(10):4306-11. doi: 10.1021/jo500009x. Epub 2014 Apr 30.
AuCl3-catalyzed formal [4 + 2]-cycloadditions between substituted allenes and N-hydroxyanilines are described. This reaction sequence comprises initial isomerizations of allenes to butadienes under N2 and subsequent oxidations of N-hydroxyanilines to nitrosoarenes under O2. CuCl2 (5 mol %) was added in the second step to increase the oxidation efficiency. The reactions are compatible with various 1,1-di- and 1,1,3-trisubstituted allenes and N-hydroxyaniline derivatives. Our experimental data reveal that the roles of AuCl3 are 3-fold, including catalytic oxidations of N-hydroxyaniline derivatives to nitrosoarenes, isomerizations of alkyl-substituted allenes to dienes, and final nitroso/butadiene [4 + 2] cycloadditions.
AuCl3 催化取代丙二烯与 N-羟基苯胺的[4 + 2]环加成反应。该反应序列包括在 N2 下丙二烯的初始异构化以及在 O2 下 N-羟基苯胺的氧化为亚硝基芳烃。在第二步中添加 CuCl2（5 mol%）以提高氧化效率。该反应与各种 1,1-二取代和 1,1,3-三取代丙二烯及 N-羟基苯胺衍生物兼容。我们的实验数据表明，AuCl3 的作用有三重，包括 N-羟基苯胺衍生物氧化为亚硝基芳烃、烷基取代丙二烯异构化为二烯以及最终的亚硝基亚胺/丁二烯[4 + 2]环加成。
