Thiadiazoles, synthesis

Tetrydamine, 352 Thalidomide, 296 Thebaine, 318 Theniurn closylate, 99 Theobromine, 456 Theophylline, 464 Thiabendazole, 352, 353 1,2,5-Thiadiazole synthesis,... 

Thiadiazoles.—Synthesis. The reaction between thiazyl fluoride (N=S—F) and hexafluorobut-2-yne gives a mixture of 3,4-bis(trifluoromethyl)-... 

The Hurd-Mori 1,2,3-thiadiazole synthesis is the reaction of thionyl chloride with the N-acylated or tosylated hydrazone derivatives 1 to provide the 1,2,3-thiadiazole 4 in one simple step. ... 

Sakya, S. M. Hurd-Mori 1,2,3-Thiadiazole Synthesis In Name Reactions in Heterocyclic Chemistry, Eds, Li, J. J. Corey, E. J. Wiley Sons Hoboken, NJ, 2005, 199—206. (Review). 

The synthesis of 1,3,4-thiadiazoIes is discussed in terms of the number of bonds being formed and by ring transformation. Thiadiazole synthesis by one-bond formation is exemplified by the cyclization of an acylated thiosemicarbazide as shown in Scheme 16. The most common two bond formation takes place via 1,3-dipolar cycloadditions presented in Scheme 23. 

A unique thiadiazole synthesis from the industrial raw materials sulfur dioxide and potassium cyanide has been reported by Ross and... 

Phenyl-l,3,4-oxathiazol-2-one (370), prepared from primary amides and tri-chloromethanesulfenyl chloride, undergoes a ready thermal elimination of carbon dioxide with the formation of the nitrile sulfide ylide (371). This can be trapped by a wide variety of unsaturated dipolarophiles, and with an alkyne provides a ready route to isothiazoles (372) (see Chapter 4.17). Applications to 1,2,4-thiadiazole synthesis are described in Chapter 4.25. Thermolysis of l,3,4-oxadiazolin-5-ones (500 C/10 mmHg) results in the loss of CO2 and generation of the corresponding nitrilimine (78JOC2037). 

Thiadiazoles, synthesis from carbon disulfide 84S797. 

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