Thiatriazole-5-thiol and Its Derivatives

Detailed directions for the preparation of the sodium salt are given by Smith. Sommer also made many qualitative observations on the properties of other salts and of the acid itself and its oxidation product, a disulfide. These observations were put on a firmer base by the extensive investigations of Browne et (see also references 50 and 51). 

When Sommer tried to prepare the potassium salt of 3 the crystal-fine product obtained exploded with violence as he spread it upon a porous plate. The potassium salt was, however, isolated and analyzed by Browne and Hoel. It is anhydrous but very soluble in water. Several other salts have been prepared. The slightly soluble heavy-metal salts are very sensitive to shock and may explode violently even under water. 

Slow thermal decomposition of the alkali metal salts of 3 takes place quantitatively in accordance with Eq. (5), where M represents an 

The free acid, l,2,3,4-thiatriazole-5-thiol, may be prepared from hydrogen azide and carbon disulfide, but the simplest way to obtain the acid is to treat a chilled solution of the sodium salt with concen- 

5-Substituent in thiatriazole ring Melting point, ° C References 

The formation of hitherto unknown or difficultly accessible types of thiocyanates by thermal degradation of S-substituted 5-mercapto- 

Tributyltin azide reacts with carbon disulfide in solution to give what is supposed to be 4-(tributyltin)thiatriazoline-5-thione because, on evaporation of the solvent, tributyltin isothiocyanate is formed.42 However, isolation of this compound does not show whether tin is coordinated to S or N in the thiatriazole since rearrangements may have taken place. 

Organometallic azides of the type [(Ph)3P]2M(N3)2 (M = Pt, Pd) react with CS2, probably with formation of 5-mercaptothiatriazole complexes.43 

Extremely shock-sensitive alkylene bis[5-thiatriazolyl]sulfides were prepared by Pilgram et al.44 45 by treating sodium thiatriazole-5-thiolate with dihaloalkane. Dichloromaleimide reacted analogously.45 

The synthesis of some new 5-benzylthiothiatriazoles by standard methods have been described.12 Nilsson et al.46 reported on the forma- 

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The isolated acid or its salts are shock- and heat-sensitive explosives [1]. Safe preparative procedures have been detailed [2]. Anhydrous salts should be handled only in small quantities and shielded from electrostatic discharge. Although names reflecting the preparation from azide are still in use (2005) the actual structure of the salts and disulfide derives from the cyclic l,2,3,4-thiatriazole-5-thiol, and the tautomeric thiatriazolidinethione forms the isolable free acid [3]. The heavy metal salts, though powerful detonators, are too sensitive for practical use [2]. 

Based on the calculations at the B3LYP/6-311-I— -G level and experimentally observed vibrational spectra for the ring and chain isomers, compounds 2 and 3, respectively (see Equation 2), it was concluded that the compounds existed in the cyclic form. The crucial fact is the absence of a stretching band at 2206 cm-1 in the experimental spectra that could, according to calculation, be associated with an azido group <1999PS201>. The experimental and theoretically calculated IR and Raman spectral data for l,2,3,4-thiatriazol-5-thiol derivatives are placed in Table 7. 

The salts of thiatriazole-5-thiol react with alkyl and acyl halides to give S-alkyl and 5-acyl derivatives. Lieber et al. formulated the acyl derivatives as 4-substituted thiatriazolines, but it has been demonstrated unequivocally that both acylation and alkylation afford the 5-substituted products. A detailed discussion of this problem has been published elsewhere (76AHC(20)145). 

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