Amino 1,2 4 triazole

Im a 1-1. round-bottomed flask, equipped with an efficient wate=r condenser, are placed 148 g. (2 moles) of ethyl formate (b.p. 52-53°) and 150 ml. of 95% ethanol. One hundred and tweruty grams (2 moles) of 85% hydrazine hydrate is added 

The residual amine in the filtrate may be isolated in the form of the hydrochloride. The combined solutions are evaporated on a steam bath, 50 ml. of concentrated hydrochloric acid is added, and heating is continued for 2 hours. On cooling, the syrupy solution crystallizes. It is triturated with 50 ml. of ethanol, and the 4-amino-l,2,4-triazole hydrochloride is filtered, washed with a little ethanol, and dried. The yield of the hydrochloride is 10-18 g. (8-15%) the salt melts at 147-148° and may be recrystallized from 95% ethanol, using 10 ml. per gram the melting point is thus raised to 151-152°. 

The reaction is very vigorous, but, if the hydrazine hydrate is added carefully, no difficulty of control is encountered. 

The combined yield of base and hydrochloride is always about 80-81%. When the amount of base is low, that of the hydrochloride is high. 

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Amino-l,2,4-triazole has been prepared by evaporating formylguanidine nitrate with sodium carbonate, and from 5(3)-amino-1,2,4-triazole carboxjdic acid-3(S) by heating above its melting point, or by a long digestion with acetic acid. ... 

Fragmentary ultraviolet spectral data are available for 3-amino-1,2,4-triazole. Early chemical data on 3,5-diamino-2-phenyl-l,2,4-triazole were interpreted on the basis of the diimino structure 201, but ultraviolet spectral evidence was later stated to favor either structure 202 or 203. ... 

Surface complexation to form a tetrahedral Co(L)X2 species is proposed to account for the adsorption of cobalt(II) chloride and bromide from acetone and ethanol solution onto silica gel modified with 3-amino-1,2,4,-triazole,526 supported by electronic and ESR spectroscopy. 

Table 16 Traceless polymer-supported synthesis of 4,5-disubstituted 3-amino-1,2,4-triazole derivatives (Scheme 5)...

AMORY, A.M, FORD, L., PAMMENTER, N.W., CRESSWELL, C.F., The use of 3-amino-1,2,4-triazole to investigate the short-term effects of oxygen toxicity on carbon assimilation by Pisum sativum seedlings, Plant Cell Env., 1992,15,655-663. 

Table 20 Ring closures to [1,2,4]triazolo[1,5-a]pyrimidines by reaction of 3-amino[1,2,4]triazoles with /3-oxo ketones, esters, nitriles, or malonic acid derivatives...

Studies have been made of the fate of 3-amino 1,2,4 triazole herbicide in soils [106], while adsorption of aminotriazole by clay minerals has been postulated, little is known of the interaction with pure clay minerals, particularly of the montmorillonite group. The importance of such reactions cannot be overemphasized in view of their bearing on the persistence of the herbicide in the soil. 

In patents, it was stated that one of the ring nitrogens of 3-amino-1,2,4-triazoles reacted with dialkyl ethoxymethylenemalonates in aqueous ethanol at room temperature (48USP2449226 49USP2476549), but Williams later proved that the amino group was involved in these reactions and that (l,2,4-triazol-3-ylamino)methylenemalonates (68)... 

Williams investigated the reactions between 3-amino-1,2,4-triazoles and EMME or 1-ethoxyethylidenemalonate (6IJCS3046 62JCS2222). He assumed that 3-amino-1,2,4-triazoles reacted with EMME or 1-ethoxyethylidenemalonate first via the primary amino group under acidic conditions, while under basic conditions, the ring nitrogen atom was involved in the first step of the cyclocondensation (61JCS3046). 

Spickett and Wright investigated the reactions of 4-substituted 3-amino-1,2,4-triazoles and EMME in acetic acid for 24-48 hr [67JCS(C)503]. Generally, they obtained [l,2,4]triazolo[l,5-a]pyrimidine-7-ones (1124) in 38-56% yields. In the case of the benzyl derivative (R = CH2Ph), the isomeric triazolo[l, 5-a]pyrimidin-5-one (1125) was also isolated from the mother liquor, in 5% yield. From the 4-ethyl and 4-phenethyl derivatives (R = Et, CH2CH2Ph), l-(l,2,4-triazol-3-yl)pyridin-2-ones (1126) were also obtained in 1-2% yields. 

In the reaction of 4-benzyl-3-amino-1,2,4-triazole and 1-ethoxyethyli-denemalonate under the previous circumstances, 7-methyl-l,2,4-triazolo[l, 5-a]pyrimidin-7-one (1127) was prepared in 10% yield [67JCS(C)503]. 

Agrawal and co-workers have reported the synthesis of A,A -bis(l,2,4-triazol-3-yl)-4,4 -diamino-2,2, 3,3, 5,5, 6,6 -octanitroazobenzene (17) (BTDAONAB) via nitration-oxidative coupling of 4-chloro-3,5-dinitroaniline (152) followed by nucleophilic displacement of the chloro groups with 3-amino-1,2,4-triazole. BTDAONAB has the unique distinction of being the most thermally stable explosive reported so far (DTA exotherm 550 °C) as compared to well known thermally stable explosives such as TATB ( 360 °C), TACOT ( 410 °C), NONA ( 440 50 °C), and PYX ( 460 °C). 

Amino-1,2,4-triazole is a useful starting material for the synthesis of many 1,2,4-triazole-based explosives. Jackson and Coburn synthesized a number of picryl- and picrylamino-substituted 1,2,4-triazoles. PATO (99) is synthesized from the reaction of 3-amino-1,2,4-triazole (98) with picryl chloride (67). ° PATO has also been synthesized from the reaction of 3-amino-l,2,4-triazole with A,2,4,6-tetranitromethylaniline (tetryl). PATO has a low sensitivity to impact and is thermally stable up to 310 °C. PATO (VOD 7469 m/s) exhibits lower performance to TATB (VOD 8000 m/s) which is the common benchmark standard for thermal stability and insensitivity in explosives. 

Agrawal and co-workers synthesized l,3-bis(l,2,4-triazol-3-amino)-2,4,6-trinitroben-zene (SDATO or BTATNB) (100) from the reaction of two equivalents of 3-amino-1,2,4-triazole (98) with styphnyl chloride (85). The performance of SDATO (calculated VOD 7609 m/s) is slightly higher than PATO while showing more insensitivity to impact. 

Amino derivatives of 1,2,3- and 1,2,4-triazoles are useful precursors to the corresponding nitro-substituted triazoles. 3-Amino-1,2,4-triazole (98) undergoes diazotization on reaction with nitrous acid the resulting diazonium salt (110) can react with a range of nucleophiles, including an aqueous solution of sodium nitrite which yields 3-nitro-1,2,4-triazole (111). Diazotization of 3,5-diamino-l,2,4-triazole (112), followed by heating with an aqueous solution of sodium nitrite, yields 3,5-dinitro-1,2,4-triazole (113). ... 

For example, the formation of mixtures of 4,5- and 4,7-dihydroisomers 45 and 46 was observed by Werman and Hartman [79] in the reaction of 3-amino-l,2,4-triazole with two equivalents of methylarylketone in the presence of ZnCl2 as a catalyst (Scheme 20). The ratios between two position isomers were from 50 50 to 74 26. However, Desenko et al. [80] established that treatment of the same starting compounds under acidic catalysis (acetic or mineral acids) yielded only 4,5-dihy-droderivatives 46 and heterocycles 47 [81]. In the latter case, the third component of the multicomponent condensation was the solvent - DMF. It is worth noting that heterocychc compounds 46 were also the products of the reaction between 3-amino-1,2,4-triazole with a,p-unsaturated ketones 48 (Scheme 20). 

It is important to note that the formation of heterocycles with participation of endocyclic nitrogen in position 4 of 3-amino 1,2,4-triazole (azolopyrimidines 49) is quite unusual, and there are only several references in literature concerning similar reaction products [1, 2]. It should be also mentioned again that the same reaction in acetic acid yielded solely carboxylic acid 30 [62] (Scheme 13). 

Scheme 22 Formation of regio-isomers in MCRs of 3-amino-1,2,4-triazole, pyruvic acid and...

On the other hand, Lipson and co-authors in their pubhcations described numerous MCRs of cyclic (3-dicarbonyl compounds and aldehydes with 5-amino-3-methylpy-razole [84], 3-amino-1,2,4-triazole [90], 3-amino-5-methyltio-l,2,4-triazole [91], 2-aminobenimidazole [92], and 2,5-diamino-l,2,4-triazole [93]. It was shown that multicomponent treatments studied in the case of these aminoazoles should proceed via preliminary formation of corresponding enamines, which were isolated and subsequently transformed into target heterocycles (Scheme 28). Intermediates... 

In continuation, the same authors published the similar efficient method for the synthesis of imidazo[l,2-b][l,2,4]triazoles, an example of which had already been known and discussed before [140]. A number of aliphatic nitriles were reacted with 3-amino-1,2,4-triazole and diverse benzaldehydes in methanol under refluxing for 15 h in the presence of ammonium chloride (Scheme 46). 

The 3-alkylthio groups in 1,2,4-thiadiazoles are difficult to replace. Thus, 3-alkylthio-l,2,4-thia-diazoles resist the action of aniline at 100°C, ammonia at 120°C, molten urea and ammonium acetate however, hydrazine attacks 3-methylthio-l,2,4-thiadiazole (142) forming 3-amino-1,2,4-triazole (143) (Equation (21)) <65AHC(5)119>. In contrast to 3-alkylthiogroups, 5-sulfonyl groups in... 

Mit aromatischen Amin-Hydrochloriden erfolgt Ringspaltung zu 1 -Aryl-2-ureido-amidi-nen oder 1-Aeylamino-guanidinen724, die zu 3-Hydroxy- bzw. 3-Amino-1,2,4-triazole n cyclisiert werden konnen726. 

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