A convenient synthesis of 5-substituted tetrahydro-1,4,3-oxathiazine 4,4-dioxides was written by Grunder-Klotz, Evelyne;Humbert, Paul;Ehrhardt, Jean Daniel. And the article was included in Heterocycles in 1993.SDS of cas: 5339-69-5 This article mentions the following:
Tetrahydrooxathiazine dioxides I (R1 = H, Me, Ph; R2 = H, Me; R3 = 4-ClC6H4, 4-MeOC6H4, CH2Ph, Bu, iso-Pr) were prepared in a 1-pot synthesis by the reaction of N-alkyl- or N-arylsulfonamide dianions with gaseous HCHO. Thus, MeSO2Cl condensed with 4-ClC6H4NH2 to give MeSO2NHC6H4Cl-4 which was reacted with 2.1 equivalent BuLi and then HCHO(g) to give I (R1, R2 = H, R3 = 4-ClC6H4). The stability and some reactions of these heterocyclic compounds were also described. In the experiment, the researchers used many compounds, for example, N-Isopropylbenzenesulfonamide (cas: 5339-69-5SDS of cas: 5339-69-5).
N-Isopropylbenzenesulfonamide (cas: 5339-69-5) belongs to amides. Compared to amines, amides are very weak bases and do not have clearly defined acid–base properties in water. On the other hand, amides are much stronger bases than esters, aldehydes, and ketones. Amides are not in general accessible by the direct condensation of amines with carboxylic acids for two reasons: first, both components are readily deactivated by a transfer of a proton from the acid to the amine and second, the hydroxy unit on the carbonyl of the acid is a relatively poor leaving group. Nevertheless, the formation of five- and six-membered rings is often surprisingly simple provided that other factors can be brought into play to assist in the condensation.SDS of cas: 5339-69-5
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics