Stereoselective\nVinylogous Aza-Pummerer Reaction of\nβ,β-Disubstituted Enesulfinamides

Treatment of multisubstituted NH-enesulfinamides\nwith\ntosyl isocyanate\n(TsNCO) at room temperature results in the formation of α-tosylcarbamoyloxy <i>N</i>-sulfenyl ketimines with high enantioselectivity. This\nprocess is believed to proceed via a vinylogous aza-Pummerer-type\nreaction pathway in which the sulfinyl oxygen atom in the enesulfinamides\nundergoes nucleophilic attack on tosyl isocyanate, triggering the\nsubsequent transformations that enable the transfer of chirality from\nsulfur to carbon.