Efficient green synthesis of a potential novel nosylation reagent and its DFT study

4-(Dimethylamino)-1-((4-nitrophenyl)sulfonyl)pyridin-1-ium chloride ([DMAPNS]+Cl−) has been designed based on DFT studies to have higher reactivity coupled with better stability than that of [DMAPTS]+Cl−. Accordingly, this novel reagent was prepared by using 1.0 equivalent of p-nitrobenzene sulfonyl chloride (1), 1.0 equivalent of DMAP (2) with higher yield (>99%), using sustainable approaches. The following greener techniques were optimized in the preparation of the novel reagent (i) less hazardous method (3rd principle of green chemistry), (ii) bio renewable (7th principle of green chemistry), 2-MeTHF solvent (Class 3 solvent), (iii) room temperature (6th principle of green chemistry), and (iv) column chromatography free methods (4th principle of green chemistry).