Triphosgene as an Efficient and Electrophilic Reagent for the One-pot Synthesis of Sulfonylsemicarbazids

1 Results Sulfonylsemicarbazide derivatives are important compounds as blowing agents in cellular rubber and plastics1]. Different methods for the preparation of these compounds are reported. For example, sulfonylsemicarbazides are prepared by reaction of sulfinic acid salt with azodicarbonamide in water2] and reaction of sulfonylchloride with semicarbazide3-4]. In these methods the yields of products are not high3-4], the solvent such as pyridine is toxic and also the sulfinic acid salt as starting material is not commercially available2]. Recently, triphosgene bis(trichloromethyl)carbonate], a crystalline solid which can be easily handled, was reported as a safe stable reagent5]. It was successfully utilized to the synthesis of large variety of organic compounds6].