1925-70-8Relevant academic research and scientific papers
Syntheses and thermal rearrangements of 2-phenyl-4-alkoxycarbonyl-1,3,4-oxadiazol-5(4H)-ones and related sulfur compounds
Golfier, M.,Guillerez, M. G.
, p. 71 - 80 (2007/10/02)
Syntheses of nine 2-phenyl-4-alkoxycarbonyl-1,3,4-oxadiazol-5(4H)-ones are described.On heating about 200 deg C, these compounds decarboxylate and give 2-phenyl-4-alkyl-1,3,4-oxadiazol-5(4H)-ones.Although many analogies suggest that the rearrangement proceeds through the cyclisation of a 1,5-dipole, arising from the decarboxylation of the heterocycle, no direct evidence for such a mechanism was obtained.On the contrary, the synthesis and the thermal rearrangement of four related sulfur compounds show that such a postulated intermediate cannot explain all the experimental results.
NOVEL AND CONVENIENT METHODS FOR THE PREPARATION OF SUBSTITUTED THIOPHENES, THIAZOLES, AND 1,3,4-THIADIAZOLE-2(3H)-THIONES FROM BIFUNCTIONAL SUBSTRATES
Thomsen, I.,Pedersen, U.,Rasmussen, P. B.,Yde, B.,Andersen, T. P.,Lawesson, S.-O.
, p. 809 - 810 (2007/10/02)
The reactions of LR (Lawesson's Reagent) with 4-oxocarboxylic acid derivatives I, N-acyl aminoacid derivatives III, and N-acyl-N'-ethoxycarbonylhydrazines V, smoothly produce substituted thiophenes II, thiazoles IV, and 1,3,4-thiadiazole-2(3H)-thiones VI.
