1,2,3,4-Thiatriazole, 6-amino

CN3S s N N N — 5-Phenyl-l,2,3,4-thiatriazole 5-amino-l,2,3,4-thiatriazole 5-phenyl-1,2,3,4-thiatriazole 3-oxide... 

By reaction of thiosemicarbazide or its 4-alkyl derivatives with nitrous acid Freund and co-workers in 1896 prepared compounds which were formulated as amino or alkylamino derivatives of the ring system 1,2,3,4-thiatriazole (1). Oliveri-Mandala, however, argued that these compounds are actually thioazides (2), and this view seems to have been generally accepted (e.g. in Beilstein s Handbuch) until... 

The most general route to 1,2,3,4-thiatriazoles involves treatment of a thiohydrazide with nitrous acid [Eq. (1)]. Thus, 5-amino-... 

From 5-chloro-l,2,3,4-thiatriazole and secondary amines Lieber et al. have prepared some 5-disubstituted-amino-l,2,3,4-thiatria-zoles. It seems possible that several other types of compounds could be prepared from 5-chlorothiatriazole, which, however, is very unstable (explosive). 

An analogous decomposition of 5-amino-l,2,3,4-thiatriazole or 5-alkylamino-1,2,3,4-thiatriazoles gives cyanamide or an alkyl-cyanamide. ... 

Accordingly, 5-substituted-amino-l,2,3,4-thiatriazoles (Tables III and IV) are formed quite generally from 4-substituted-thiosemicarb-azides. When the substituent is an aryl group these initial products are isomerized to 5-mercaptotetrazoles on treatment with alkali whereas this is not the case when the substituent is an alkyl group. 

As shown by Oliveri-Mandalli,and by Lieber et al., 5-sub-stituted-amino-l,2,3,4-thiatriazoles are also formed by reaction of isothiocyanates with hydrazoic acid. When sodium azide is used instead of the free acid the isomeric mercaptotetrazoles are formed. 

On treatment of 5-amino-l,2,3,4-thiatriazole with concentrated hydrochloric acid Freund and Schander obtained a hydrochloride of a sulfur-containing substance which was thought to be a three-membered ring compound [cf. Eq. (19)]. The possibility that it might be a dimer with a six-membered ring was, however, left open. 

However, Sahasrabudhey thinks that the compound formed from 5-amino-1,2,3,4-thiatriazole does not have the composition CSN2H3CI, but (CSN2H4C1)2, and is in fact the dihydrochloride of formamidine disulfide, the oxidation product of thiourea. This con-... 

Lieber et have come to the same conclusion by an investigation of the ultraviolet spectra and dipole moments of 5-amino-, 5-methyl-amino-, and 5-dimethylamino-l, 2,3,4-thiatriazole. The dimethylamino derivative, in which no tautomerism is possible, shows the same characteristic absorption near 250 m/A as the unsubstituted compound and the monomethyl derivative. The dipole moments of the three compounds differ very little. These moments are quite large (5.8 Debye), showing that ionic resonance forms of type 9 contribute considerably to the structure of these compounds. 

The most characteristic feature of the infrared spectra of all 5-mono- and -di-substituted-amino-l,2,3,4-thiatriazoles is a strong band in the 1540-1590 cm range, which without doubt is due to the C=N and N=N stretching vibrations of the heteroaromatic ring system. Various infrared bands between 889 and 1122 cm have been assigned to skeletal vibrations of the thiatriazole ring and a band... 

Table III Since this table was prepared R. G. Dubenko, I. N. Berzina, and P. S. Pel kis [Zh. Obshch. Khim. 33, 274 (1963)] have described eighteen 5-aryl-amino-1,2,3,4-thiatriazoles of which only five are listed in Table III. The melting points given for these five compoimds differ considerably from those listed in Table lil o-tolyl, 117-118° p-tolyl, 151-152° o-methoxyphenyl, 109-110° p-methoxyphenyl, 129-130° and p-chlorophenyl, 162-163°.

Only amino tautomeric forms were also observed for the derivatives of 5-amino-l,2,3,4-thiatriazole 97 [76AHC(S1), p. 440 84CHEC-I(6)579]. 

Acetyl-4-(4/-sulfophenyl)-3-tetrazene, 2982 Aluminium azide, 0082 Aluminium tetraazidoborate, 0059 Amino guanidine, 0507 1-Amino-3-nitroguanidine, 0495 5-Aminotetrazole, 0461 5-Amino-l,2,3,4-thiatriazole, 0413... 

Amino-l,2,3,4-thiatriazole (207) when acylated with 0-aryl chlorothioformate (208) transforms into an unstable 5-aryloxy-3-imino-l,2,4-dithiazole hydrochloride (209). Acylation of this compound produces 2,5-bis(aryloxy)-l,6,6aA -trithia-3,4-diazapentalene ([210), which may be obtained more conveniently by acylating (207) with two equivalents of (208) (Scheme 44) <89M( 120)997, 90JPR208>. 

Treatment of 5-substituted amino-1,2,3,4-thiatriazoles (283) with aqueous base results in competitive rearrangement to 5-thiotetrazoles (284) and fragmentation to isothiocyanates (285) and... 

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