3.5- Diamino-l,2,4-triazoles

Similarly to aminoazoles, diaminoazoles prefer their amino forms 210 for 3,5-diaminopyrazole [76AHC(S1), p. 460 84CHEC-I(5)167 96CHEC-11(3)1] 211 for 3,5-diamino-l,2,4-triazole and 212 for 3,5-diaminoisothiazole [76AHC(S1), p. 460]. Ilie triamino structure 213 was proven by an X-ray crystallographic study of 4-aminoquinazine hydrobromide [73JCS(P2)lj. 

The regioselective alkylation and acylation of 3,5-diamino-l,2,4-triazole 19 using a simple protecting group strategy has been described in detail <2006RJA624, 2006ZPK632>. 

The reactions of 5-methylthio-3-amino- or 3,5-diamino-l,2,4-triazole and diethyl 1-ethoxyethylidenemalonate in boiling ethanol in the presence of sodium ethylate for 1.5-3.5 hr gave l,2,4-triazolo[l,5-a]pyrimidin-7-ones (1123, R = MeS, NH2, R1 = Me) in 44% and 20% yields, respectively. The reaction of 5-methylthio-3-amino-l, 2,4-triazole (R = MeS) and 2-ethoxyethylidenemalonate in boiling pyridine for 4 hr gave 1,2,4-tria-zolo[l,5-a]pyrimidin-5-one (1122, R = MeS, R1 = Me) in 12% yield (61JCS3046). 

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). ... 

Lipson et al. in several publications [91-93] in the reactions of dimedone and aromatic aldehydes with 2-aminobenzimidazole, 3,5-diamino-l,2,4-triazole, and 3-amino-5-methyltio-l,2,4-triazole described a formation of angular tri- and four-cyclic heterocycles as minor reaction products. However, aldehydes did not participate in these MCRs and the solvent (DMF) acted as a carbonyl component... 

In the case of 3,5-diamino-l,2,4-triazole, the situation was different refluxing in DMF gave two isomers 85 and 86 while application of methanol or iso-propanol as reaction medium allowed obtaining only one reaction product - heterocycles 85 (Scheme 36) [115]. Selective MCR with the formation of corresponding 7-pyrimi-dinenone was also observed when 3-amino-1,2,4-riazoles and Meldrum s acid reacted with ketones instead of aldehydes. 

Along with the formation of dihydropyrimidine derivatives, an unusual directions of multicomponent treatment of 2,4-dioxobutanoates with aldehydes and several aminoazoles were described by Gein and co-authors [151]. Thus, fusion of carbonyl compounds with 3,5-diamino-l,2,4-triazole gave as usual for this type... 

Two series of dyes are derived from 3,5-diamino-l,2,4-triazole [1455-77-2, also known as guanazole. The monoazo dyes form red diazadimethine dyes (e.g., 35) after alkylation [88],... 

Nitro-l,2,4-triazole (45%) [451] and l-methyl-4-cyano-5-nitropyrazole (42%) [452] were isolated during the oxidation of corresponding aminoazole derivatives by a solution of hydrogen peroxide in trifluoroacetic acid. One of the amino groups in l-acyl-3,5-diamino-l,2,4-triazole is oxidized by hydrogen peroxide in the presence of sodium tungstate [453] (Scheme 59). 

Dinitro-l,2,4-triazole has been synthesized from 3,5-diamino derivative with sodium nitrite excess [667], and the protocol was proposed for the preparation of 3,5-dinitro-l,2,4-triazole from dicyanodiamide and hydrazine without isolation of 3,5-diamino-l,2,4-triazole. 

N,N -Dimethylacetamide (DMAc) (Aldrich, HPLC grade) was used without further purification. Acetic anhydride (BDH) was pre-dried over anhydrous sodium acetate. Pyridine (Aldrich, anhydrous) was distilled from KOH prior to use. Poly(maleic anhydride-co-octadec-l-eneXl l) (Polysciences), as a polymeric stabilizer, was used as supplied. Paraffin oil (A.J. Beveridge Ltd., liquid paraffin 5LT) was used as a suspending medium. Pyromellitic dianhydride (1,2,4,5-benzenetetracarboxylic dianhydride) (Aldrich) was recrystallized from butan-2-one before use. p-Phenylenediamine (Aldrich) and 2,6-diaminopyridine (Aldrich) were recrystallized from ethanol. 3,5-Diaminobenzoic acid (Aldrich) and 2,5-diaminobenzene sulfonic acid (Aldrich) were recrystallized from water and heated at HOT) under vacuum to remove water. 3,5-Diamino-l,2,4-triazole (Aldrich) and tris(2-aminoethyl)amine (Tokyo Kasei) were without further purification. 

The incorporation of pyridine or triazole improves the adhesion between poly(imide)s and copper.Poly(3,3, 4,4 -benzophenone tetracarboxylic dianhydride-3,5-diamino-l,2,4-triazole) (BTDA-DATA) contains the triazole moiety as repeating units. Poly(4,4 -oxydiphthalic anhydride-1,3-aminophenoxybenzene-8-azaadenine) (ODPA-APB-8-AA) bears the triazole moieties at the end." BTDA-DATA starts to decompose at 350°C. However, ODPA-APB-8-AA starts to decompose at 400°C. The polymers have been tested as adhesives for copper surfaces. The adhesion is increased by the formation of copper complexes. 

Poly(3,3, 4,4 -benzophenone tetracarboxyUc dianhydride-3,5-diamino-l,2,4-triazole), 317 C120-PPP... 

A few amino (Am) functionalized MOFs have been obtained by direct self-assembly using Am-derived ligands, such as 2-aminoterephthalic add or 3,5-diamino-l,2,4-triazole. Such Am-MOFs have functionalities on their walls, which... 

Lately Garg and Shreeve suggested a simple synthesis of trifluoromethanesul-fonamide derivatives of 3-amino- and 3,5-diamino-l,2,4-triazoles 88, 89 from the corresponding aminoazoles and trifluoromethanesulfonyl fluoride [86],... 

---