Cobalt-Catalyzed Direct C–H Carbonylative Synthesis of Free (<i>NH</i>)-Indolo[1,2-<i>a</i>]quinoxalin-6(5<i>H</i>)-ones
Qian Gao, Jiaming Lu, Lingyun Yao, Siqi Wang, Jun Ying, Xiao‐Feng Wu
Abstract
A cobalt-catalyzed direct C–H carbonylative reaction of N-(2-(1H-indol-1-yl)phenyl)picolinamides for the synthesis of (NH)-indolo[1,2-a]quinoxalin-6(5H)-one skeletons has been developed. Using benzene-1,3,5-triyl triformate (TFBen) as the CO source and picolinamide as the traceless directing group, various free (NH)-indolo[1,2-a]quinoxalin-6(5H)-ones were obtained in good yields (up to 88%). Additionally, a series of product derivatizations were demonstrated, and the core fragment of PARP-1 inhibitor C can be readily constructed by this protocol.
Topics & Concepts
ChemistryCatalysisCobaltMedicinal chemistryCarbonylationCombinatorial chemistryStereochemistryCarbon monoxideOrganic chemistryCatalytic C–H Functionalization MethodsSynthesis and Biological EvaluationCatalytic Cross-Coupling Reactions