Chemoselective Cleavage of Acylsulfonamides and Sulfonamides by Aluminum Halides.

The chemoselective cleavage of C-N bonds of amides, sulfonamides, and acylsulfonamides by aluminum halides is described. AlCl3 and AlI3 display complementary reactivities toward N-alkyl and N-acyl moieties. N-Alkylacylsulfonamides, secondary N-(tert-butyl)sulfonamides, and tertiary N-(tert-butyl)amides undergo N-dealkylation upon treatments with AlI3 generated in situ from aluminum and iodine in acetonitrile. In contrast, AlCl3 preferentially cleaves N-acyl groups of tertiary and secondary sulfonamides.