537012-75-2Relevant academic research and scientific papers
Synthesis and structure of novel 1λ4,2,6-thiadiazines
Diederich, Wibke E.,Haake, Manfred
, p. 3817 - 3830 (2007/10/03)
S,S-Disubstituted sulfodiimines 9 are known to be versatile building blocks for the synthesis of various sulfur-nitrogen-containing heterocycles. Addition-condensation reactions of 9 with three different activated carbonylsubstrates 14-16 lead to several new 1λ6,2,6-thiadiazine-3-ones 17-20. S-Debenzylation via a novel synthetic approach utilizing different electrophiles such as TMSCl, Alk3O+BF4-, Tos2O, and Mes2O gives rise to a variety of so far hardly known 1λ4,2,6-thiadiazine- 3-ones 25 and 26. Structure elucidation reveals NH/CH tautomers in solution as well as a tetrahedral asymmetric sulfur attached to the conjugated planar N/C skeleton. The structural features of the 1λ4,2,6-thiadiazines 25 and 26 as well as their reactivity toward certain electrophiles will be discussed in detail. Alkylation with Alk3O+BF4- preferably results in formation of the 3-alkoxy- 1λ4-2,6-thiadiazines 29. In the presence of acid or base, also the N-2-alkyl isomers 30 are formed. Mesylation of 26 with methanesulfonic acid anhydride followed by aminolysis furnishes a variety of the desired heterocycles 5 in moderate overall yield.
