Synthesis and some reactions of derivatives of 5-(1,2,3-thiadiazol-4-yl)furan-2-carboxylic and 3-[5-(1,2,3-thiadiazol-4-yl)fur-2-yl]acrylic acids

摘要

Alkyl 5-(1,2,3-thiadiazol-4-yl)furan-2-furoate and 3-[5-(1,2,3-thiadiazol-4-yl)fur-2-yl]acrylate were synthesized via cyclization of carbethoxyhydrazones of acetyl derivatives of furan-2-carboxylic and 3-(2-furyl)-acrylic acids under the conditions of the Hurd-Mori reaction. Corresponding acids, acid chlorides, amides, furoyl hydrazide and acryloyl azide were prepared. It was shown that in all above-mentioned substances furylthiadiazole fragment is thermally stable. Treating of methyl 5-(1,2,3-thiadiazol-4-yl)furan-2-furoate with morpholine in the presence of potassium hydroxide leads to the cleavage of thiadiazole ring with the liberation of nitrogen and the formation of [5-(methoxycarbonyl)fur-2-yl]acetic acid morpholide.