1.2.3.4- Tetrazoline-5-thione, structure

It appears quite probable that this reaction occurs by the same mechanism as the reaction of nitrous acid with thiosemicarbazides and of sodium azide with isothiocyanates. The primary reaction product is a thiocarbamoyl azide (CCXIII) to which, however, the cyclic structure of a 5-amino-l,2,3,4-thiatriazole (CCXIV) is attributed. In alkaline medium these compounds rearrange to the corresponding 1 -substituted-Zla-tetrazoline-5-thiones (CCXII) 236, 237). A survey of these compounds, prepared from the dithiocarbamic acid esters, is given in Table 33. 

Scheme 36 The reaction of organotin azides 181 and 182 with phenyl isothiocyanate (183) gives l-phenyl-4-organotin-A -tetrazoline-5-thiones 184 and 185 and their tautomers (S-organotin)-l-phenyl-5-thiotetrazoles 186 and 187. The latter are the confirmed structures of the formed intermediates that upon treatment with dilute hydrochloric acid, provide l-phenyl-A -tetrazoline-5-thione (188) [137,138]...

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