Preparation of unsymmetrical sulfonylureas from N,N'-sulfuryldiimidazoles.
The synthetic methods reported in the literature for the preparation of sulfonylureas tend to be restricted in scope or unsuitable for use in parallel synthesis. We have developed a method for preparing sterically congested sulfonylureas based on N,N'-sulfuryldiimidazole that is both convenient and amenable to parallel synthesis. Sequential activation by way of alkylation of the imidazole group using methyl triflate followed by nucleophilic displacement with a variety of amines and anilines afford the unsymmetrical sulfonylurea. Sulfonylureas prepared from anilines were obtained in high yields using N,N'-sulfuryldiimidazole, while the somewhat more sterically congested analogue, N,N'-sulfurylbis-2-methylimidazole, proved to be superior for alkylamines.
Beaudoin
Serge
S
Department of Chemistry, Icagen Inc., P.O. Box 14487, Research Triangle Park, North Carolina 27709, USA. sbeaudoin@icagen.com
Kinsey
Kenneth E
KE
Burns
James F
JF