Dipolar cycloaddition reactions of quinoxalin-3(4H)-one 1-N-oxides
Abstract
Demonstrating their reactivity as 1,3-dipoles in cycloaddition reactions, quinoxalin-3(4H)-one 1-N-oxide (3a) and its N-methyl derivative (3b) react with the aryl isocyanates (4a and b) to give the corresponding 2-arylaminoquinoxalin-3(4H)-ones (6a–c); similarly, reaction with benzyne affords the 2-(o-hydroxyphenyl)-quinoxalin-3(4H)-ones (9a and b).