Arylsulfonyl isocyanates are commonly used for the production of arylsulfonyl carbamates and ureas, finding many commercial uses. Isocyanates are toxic and have usually been prepared using processes that require the handling of dangerous chemicals such as phosgene. Dimethylaminopyridinium carbamoylides (3a–d and 25) have been designed as new, safer and non-hazardous substitutes of arylsulfonyl isocyanates and the previously unreported benzimidazol-1-yl isocyanate.