Synthesis and Physicochemical Properties of 1,2,6-Thiadiazine 1,1-Dioxides. A Comparative Study with Pyrazoles

Article abstract of DOI:10.1021/jo00342a033

The chemical and structural properties of 18 1,2,6-thiadiazine 1,1-dioxides have been studied.By comparison with the corresponding pyrazoles it could be established that there are some analogies between pyrazoles and thiadiazine 1,1-dioxides, but because of the great difference in aromaticity, both series of heterocycles behave quite differently in other cases.However, a rough parallelism is observed in the tautomeric equilibrium, the 13C chemical shifts, and the reactivity of the 4-position.As a consequence, the hypothesis will be made that these similarities are general and could be extended to a whole variety of heterocyclic and alicyclic structures.