into isatinylidenes (7,9–13, 17–19) by dehydration with 4‐toluenesulfonic acid. The dimer‐type compounds (14, 20) were also isolated in a few cases. The obtained isatinylidenes were transformed into 3‐spiro‐cyclopropane‐oxindoles (21–32) with dimethyloxosulfonium methylide. Compound 22 shows protective effects against hypobaric hypoxia and triethyltin induced brain edema.
Iodine-catalyzed efficient synthesis of azaarene substituted 3-hydroxy-2-oxindole derivatives through sp3 C–H functionalization
作者:Srinivasu V.N. Vuppalapati、Yong Rok Lee
DOI:10.1016/j.tet.2012.07.051
日期:2012.9
Iodine-catalyzed benzylic sp3 C–H bond functionalization of lutidines or picolines to isatins is described. This synthetic method provides a rapid entry towards biologically interesting 3-azaarene substituted 3-hydroxy-2-oxindole derivatives.