Silver-catalyzed nitrene insertion enables the formation of benzosultams in good yield and with regioselectivity complementary to other transition metal nitrene-transfer catalysts. Preferential formation of six-membered benzosultam rings predominates for alkyl-substituted benzenesulphonamide precursors. Ligand-controlled tunability is also achieved for benzenesulphonamides with γ-branched alkyl substituents. Mechanistic probes suggest that the reaction pathway differs depending on whether a α (benzylic) or β (homobenzylic) C-H bond undergoes amidation, as well as the catalyst identity.
class="Chemical">Silver-catclass="Chemical">n class="Chemical">alyzed nitrene insertion enables the formation of benzosultams in good yield and with regioselectivity complementary to other transition metal nitrene-transfer catalysts. Preferential formation of six-membered benzosultam rings predominates for alkyl-substituted benzenesulphonamide precursors. Ligand-controlled tunability is also achieved for benzenesulphonamides with γ-branched alkyl substituents. Mechanistic probes suggest that the reaction pathway differs depending on whether a α (benzylic) or β (homobenzylic) C-H bond undergoes amidation, as well as the catalyst identity.