Crystal Structure Analysis and Reactivity of N-Alkyl- and N-Acyldioxathiazinanes

Cyclic sulfamidates have served as reactive electrophiles for the synthesis of various products, including alkaloids, substituted amines, amino acids and lactams.N-Acyl dioxathiazinanes exhibit enhanced reactivity relative to their unsubstituted and N-alkyl counterparts, and were previously suggested to be more reactive due to carbamoylation of the -NH moiety generating an electron withdrawing effect.Probing this enhanced reactivity by the synthesis and structural analysis of N-Boc-and N-PhF-dioxathiazinanes using NMR spectroscopy, X-ray diffraction, and DFT calculations, we now describe a unique, reactive twisted conformation in N-acyl dioxathiazinanes.