A palladium-catalyzed reaction for the synthesis of benzosultams from allenes and 2-iodobenzenesulfonamides in poly(ethylene glycol) medium is described. This route is compared with a second method involving an internal Heck reaction of alkene-functionalized 2-iodobenzenesulfonamides. Key products were characterized by single-crystal X-ray crystallography.
Key words
palladium - catalysis - allenes - sulfonamides - green chemistry