Silver-mediated Room Temperature Reactions for the Synthesis of N -α-Ketoacyl Sulfoximines and N -α,β-Unsaturated Acyl Sulfoximines.

Here, we report a silver-mediated coupling of acetylenes with sulfoximines to synthesize N -α-ketoacyl sulfoximines and N -α,β-unsaturated acyl sulfoximines. The reactions are performed under an open atmosphere using the oxidant K 2 S 2 O 8 and the ligand 2,2-bipyridyl. However, the fate of the product formation is controlled by the type of substrate used. The coupling between aryl acetylenes and sulfoximines afforded the N -α-ketoacylsulfoximines, while the alkyl acetylenes provided the N -α,β-unsaturated acyl sulfoximines. Controlled experiments reveal the differential reactivity patterns of substrates. The labeling 18 O experiments showed that water is the source of the incoming oxygen atom for the keto group of N -α-ketoacyl sulfoximines and N -α,β-unsaturated acyl sulfoximines.