Iridium(III)-Catalyzed C–H Cyclization of Sulfoximines with Diazo Meldrum’s Acids for the Synthesis of Cyclic Sulfoximines

Abstract

Iridium(III)-catalyzed C–H cyclization of sulfoximines with diazo Meldrum’s acid provided cyclic sulfoximines with a carbonyl group in good to excellent yields. These compounds were easily converted into unsubstituted and arylated sulfoximines. Moreover, the vinyl triflates obtained from the cyclic sulfoximines underwent palladium(II)-catalyzed cross-coupling reactions with a variety of aryl, arylalkynyl, and heteroatom (N and S) nucleophiles, affording a wide range of monosubstituted sulfoximines in high yields.

Synthesis of Benzo[e][1,4,3]oxathiazin-3-one 1-Oxides from NH-S-(2-Hydroxyaryl)sulfoximines

“…Finally, Williams and Cram reported on benzo­[ e ]­[1,2]­thiazin-3­(4 H )-one 1-oxides such as III , in which one of the nitrogens of the aforementioned heterocycles was formerly substituted with a methylene unit . Many publications followed these seminal contributions, and subsequent work approaching such cyclic sulfoximine derivatives made use of breakthrough methods such as C–H bond functionalization and asymmetric catalysis . Surprisingly, to the best of our knowledge, structurally related benzo­[ e ]­[1,4,3]­oxathiazin-3-one 1-oxides IV , characterized by having an oxygen instead of a nitrogen or methylene in the heterocycle, are still unknown .…”