A novel and highly efficient cascade synthesis of sulfonated quinoline dione derivatives from N-(2-cyanoaryl) methylacrylamides and sulfonylhydrazides in good yields is described. The reaction proceeds through radical addition, cyclization, and imine hydrolysis, in which one new C–C bond and one C![[double bond, length as m-dash]](http://www.rsc.org/images/entities/char_e001.gif)
O bond were formed.
