N-Sulfonyloxaziridines (Davis’ oxaziridines) can be synthesized by reacting the corresponding N-sulfonylimines with aqueous sodium hypochlorite in acetonitrile without any catalyst. The pH of the aqueous sodium hypochlorite is crucial to obtain the product in high yield. Optimized conditions are presented that allow synthetically useful Davis’ oxaziridines to be easily obtained in up to 90% yields from the corresponding imines by using inexpensive, stable, environmentally friendly sodium hypochlorite pentahydrate crystals as the oxidant, with high reproducibility.

Synthesis of sulfonyl halides using sodium hypochlorite pentahydrate (NaOCl•5H2O) crystals was studied in detail, considering the reaction rate and yield of the desired product. NaOCl•5H2O reacted with disulfides or thiols in acetic acid to produce sulfonyl chlorides. The yields of the desired sulfonyl chlorides were enhanced when the reaction was performed in (trifluoromethyl)benzene under a CO2 atmosphere. The generation of hypochlomous acid (HOCl) was essential for both reactions. Similarly, sulfonyl bromides were prepared via the reaction of disulfides or thiols with sodium bromide and NaOCl•5H2O crystals in acetic acid owing to the generation of hypobromous acid (HOBr). However, the reaction could not proceed in (trifluoromethyl)benzene under a CO2 atmosphere because bromine (Br2) was produced instead of HOBr.