Tetramethyl thiophenetetracarboxylate

Michael, as early as 1895, reported the reaction of elemental sulfur with DMAD to give tetramethyl 2,3,4,5-thiophenetetracarboxylate (327)... 

Franz and Black539 have studied the thermolysis and photolysis of l,3,4-oxathiazol-2-one (l).530 This compound is thermally labile and yields benzonitrile and sulfur instead of the expected phenyl isocyanate and carbonyl sulfide. It is probable that benzonitrile sulfide (3) is an intermediate and this appears to be confirmed by formation of the adduct 4 in 90% yield when 1 is heated with 2 moles of DMAD at 130° in chlorobenzene. Heating a mixture of benzonitrile and sulfur with DMAD gave tetramethyl thiophenetetracarboxylate (6), also obtained without the nitrile. The formation of the isomeric isothiazoles 7 and 8 from 1 and EP531 is similar to the production of the corresponding... 

C12H111N2, Azobenzene, cobalt and palladium complexes, 26 175, 176 manganese complex, 26 173 C12H11N, Pyridine, 2-(phenylmethyl)-, palladium complex, 26 208-210 C12H11P, Phosphine, diphenyl-, manganese complex, 26 158, 226-230 ruthenium complex, 26 264 Ci2H,20,S, Thiophenetetracarboxylic acid, tetramethyl ester, 26 166 C 2H,5N, Naphthalenamine, A ,iV-dimethyl-, lithium complex, 26 154 Cj2Hih, Benzene, hexamethyl-, ruthenium complex, 26 181, 182... 

C 2H,20gS, Thiophenetetracarboxylic acid, tetramethyl ester, 26 166 C,2H,5N, Naphthalenamine, Af,Af-dimethyl-, lithium complex, 26 154... 

SOOSP2C4JH34, Osmium, carbonyl(S-thioxo- 1,3-pentadiene- l,S-diyl-C, C ,S) bis(triphenylphosphmeK 26 188 S02C7Hg, Benzenesulfonic acid, 4-methyl-, rhodium complex, 27 292 S04PC(H 2, 2-Butenedioic acid, 2-(dimethylphosphinothioylK dimethyl ester, manganese complex, 26 163 SOgCijHij, Thiophenetetracarboxylic acid, tetramethyl ester, 26 166 SO,oOS]C,o. Osmium, /ij-carbonylnona-carbonyl- 3-thio-tri-, 26 305 SOjoOsjCigHt, Osmium, (it-... 

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