SN2 substitution reaction of 2-C-acetoxymethyl glycals catalyzed by iodine: a novel synthesis of 2-C-N-arylamidomethyl glycals

The reaction of 2-C-acetoxymethyl glycals with N-aryl amides such as N-aryltosyl amine, p-toluenesulfonamide, and t-butoxycarbonyl amine in the presence of a catalytic amount of iodine affords a novel class of 2-C-N-arylamidomethyl glycals through direct attack at the C-2 position bearing the acetyl group under mild reaction conditions. The use of iodine makes this method simple, convenient, and cost-effective. This is the first report on nucleophilic substitution of 2-C-acetoxymethyl glycals with N-aryl amides using molecular iodine as a catalyst.