A straightforward multicomponent sulfonamidation of nitroarenes,sodium metabisulfite and boronic acids was established under transition-metal-free conditions to access diverse sulfonamides from readily available and low-cost materials modularly.Inorganic salt sodium metabisulfite not only served as a sulfur dioxide source,but also played a key role for both activator and reductant during sulfonamidation.Notably,naturally occurring biomolecules and pharmaceuticals with multiple heteroatoms and sensitive functional groups were inten-sively investigated in this transformtion providing versatile sulfonamides collectively.Further mechanistic studies demonstrated that nitrosoarene is the key intermediate,and the activation of boronic acid is the rate-determining step in the transformation.