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1,2,3-Triazoles, 1,5-diamino

In their efforts to prepare purine ring analogs for biological studies, Temple and co-workers reported on the 85% conversion of diamino-1//-l,2,3-triazolo[4,5-c]pyridine 57 under basic condition to give the fused triazole diamino-3//-l,2,3-triazolo[4,5-6]pyridine 58. This reaction was shown to proceed through a diazo intermediate. [Pg.563]

For the preparation of triazolopyrimidines three main types of synthesis are in use. The first of these proceeds from a pyrimidine derivative (especially the 4,5-diamino derivatives) and closes the triazole ring. The second method proceeds, on the contrary, from derivatives of u-triazole to close the pyrimidine ring. The third method finally is one which yields the derivatives through substitution or replacement of substituents in compounds prepared by one of the first-named procedures. [Pg.239]

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. [Pg.239]

According to X-ray data, 2,5-diamino-l,3,4-triazole retains its diamino form in the heterovalent cobalt complex 375 (91IC4858) and in the polymeric complex with manganese thiocyanate (93ICA53). [Pg.291]

Attempted dehydrocyclization of the 6-acylhydrazinopyrimidine 65 by heating with polyphosphoric acid led, instead, to pyrimidine ring rupture, yielding the l,l-diamino-2-nitro-2-(3-phenyl-l,2,4-triazol-5-yl)ethene 66. Cyclocondensation of the latter with triethyl orthoformate gave the fully aromatic triazolopyrimidine 67 (94JHC1171) (Scheme 23). [Pg.356]

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. ... [Pg.73]

Acenaphtheno[l,2-e][l,2,4]triazolo[4,3-h][l,2,4]triazine 747 was prepared (79AP147) by cyclizing 3-hydrazinoacenaphtheno[l,2-e][l,2,4]tria-zine 746 with formic acid. Reaction of 746 with sugars gave the hydrazones, which cyclized with iron(III) chloride to give 748 (93BCJ00). Similarly, the acetaldehyde derivative of 746 was cyclized to 748. The structure of 748 (R = Me) rather than 747 (R = Me) was deduced by unequivocal synthesis of the latter by condensation of acenaphthenequinone with 3,4-diamino[l,2,4]triazole (Scheme 155). [Pg.132]

Computational methods were employed to predict molecular vibrations in 3-mercato-l,2,4-triazole 18 and 3,5-diamino-1,2,4-triazole 19 in order to fully assign the Fourier transform infrared (FTIR) and FT-Raman spectra of these molecules <2004SAA709, 2005SAA261>. [Pg.162]

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>. [Pg.173]

Table 22 One-pot synthesis of 3,5-diamino-1,2,4-triazole derivatives (Equation 39) ... Table 22 One-pot synthesis of 3,5-diamino-1,2,4-triazole derivatives (Equation 39) ...
The reaction of l,5-diamino-3-/ft7-butylpyrazole 232 with carbon disulfide affords 6-fef7-butylpyrazolo[l,5-+ [l,2,4]triazole-2-thione 233 (unreported yield) (Equation 71) <2003OBC4268>. [Pg.265]

Triazolotriazepinones 475, obtained by reaction of 4,5-diamino-3-aryloxymethyl-l,2,4-triazoles 474, on heating with acetic anhydride undergo ring contraction reaction to yield l-acetyl-3-aryloxymethyl-6-methyl-pyrazolo[5,l-f][ 1,2,4]triazoles 476 (Scheme 54) <2003IJC(B)2054>. This type of transformation has been previously documented by other authors <1974JHC751>. [Pg.286]

A condensation reaction taking place between the a-diketone 208 and 3,4-diamino[l,2,4]triazole 209 has been applied for the synthesis of the pentacyclic fused triazole 210 <1994BCJ149>. The transformation was carried out in ethanol in the presence of sodium acetate and acetic acid in high yield (71%). [Pg.877]

All procedures for ring closure to the title ring system by cyclization of the six-membered ring utilize the reactivity of 3,4-diamino[l,2,4]triazoles 209 these compounds can easily react with bifunctional reagents bearing these functional groups in adjacent positions. [Pg.877]

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). [Pg.244]

Imidazolidinium salts can also be transformed into the corresponding diamino ortho-esters by alkaline alkoxylate, and upon alcohol elimination at elevated temperature the imidazolidin-2-ylidenes can be trapped. The reaction of tria-zolium salts with sodium methanolate in methanol yields 5-methoxy-4,5-dihydro-IH-triazole which also eliminates methanol upon heating in vacuo. The resulting triazolin-5-ylidenes can either be isolated or trapped by an appropriate metal precursor [Eq. (19)]. Benzimidazolin-2-ylidenes are similarly accessible by this route. [Pg.19]

Phosphorylated 2,3-diamino-2//-indazoles (172) are well suited for the annulation of a 1,2,4-triazole ring by a combination of an aza-Wittig and an intramolecular trapping reaction. As shown in Scheme 66, CS2 and CO2 are good reaction partners in the case of acid halides, however, no ring closure occurs, and 173 was obtained (89TL6237 90JOC4724). [Pg.197]

Interest in polynitroarylenes has resumed over the past few decades as the demand for thermally stable explosives with a low sensitivity to impact has increased. This is mainly due to advances in military weapons technology but also for thermally demanding commercial applications i.e. oil well exploration, space programmes etc. Explosives like 1,3-diamino-2,4,6-trinitrobenzene (DATB) (13), l,3,5-triamino-2,4,6-trinitrobenzene (TATB) (14), 3,3 -diamino-2,2, 4,4, 6,6 -hexanitrobiphenyl (DIPAM) (15), 2,2, 4,4, 6,6 -hexanitrostilbene(HNS, VOD 7120 m/s, = 1.70 g/cm ) (16) and A,A -bis(l,2,4-triazol-3-yl)-4,4 -diamino-2,2, 3,3, 5,5, 6,6 -octanitroazobenzene (BTDAONAB) (17) fall into this class. TATB is the benchmark for thermal and impact insensitive explosives and finds wide use for military, space and nuclear applications. [Pg.128]

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). [Pg.177]

Boyer and Gunasekaren reported the synthesis of the furazan-based heterocycle NOTO (44), which contains 50 % by mass of nitrogen and is a liquid at room temperature. The flve-step synthesis of NOTO (44) starts from the diazotization of 4,4 -diamino-3,3 -azoxyfurazan (DAAF) (27), followed by reaction with sodium azide to form the diazide (42). Heating the diazide (42) as a solution in acetonitrile induces cyclization to the triazole (43) and this is followed by reduction and oxidation of the remaining azide group to complete the synthesis of NOTO (44). [Pg.300]

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). ... [Pg.309]

Laval and Vignane reported the synthesis of the nitrotriazole (124) from the reaction of 3-nitro-1,2,4-triazole with 3,5-diamino-l-chloro-2,4,6-trinitrobenzene. The nitrotriazole (124) is a useful secondary high explosive, exhibiting high performance and a low sensitivity to impact. [Pg.311]

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... [Pg.59]

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... [Pg.60]

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. [Pg.66]

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... [Pg.78]

Direct amination of benzo[l,2-aqueous base with hydroxylamine-0-sulfonic acid gives a mixture of three diamino derivatives and two monoamino derivatives (Equation (15)). The combined yields of diamino and monoamino products are 45% and 48%, respectively. The three diamino derivatives can be separated by fractional crystallization from ethanol <86JOC979>. A-Amination of triazoles can also be achieved by treatment with NaH in DMF followed by O-amino-2,4-dinitrophenol <85TL335> or 0-(mesitylsulfonyl)hydroxyamine (9lJCS(Pl)2045>. [Pg.43]

Arylbenzotriazoles (797) are prepared via 2-nitro- and 2-amino-diphenylamines (Scheme 161). The 2-nitrodiphenylamines (796) are prepared from the appropriate aniline by reaction with 2-fluoronitrobenzene in the presence of KF <808215,85JCS(Pl)2725>. Azo-coupling of 2-amino-1-cyano-azulene (798) with p-tolyldiazonium chloride gives (799) (Scheme 162). Catalytic reduction of (799) quantitatively yields the diamino derivative (800), which on diazotization affords 9-cyano-azuleno[l,2-J]triazole (801) in 77% yield <85TL335>. [Pg.114]

Oxidation of 3,5-diamino-4-arylhydrazonopyrazoles (802) with lead tetraacetate gives 2-aryl-4-cyano-2//-l,2,3-triazoles (803) in moderate yield (Equation (75)). A mechanism involving pyr-azolotriazole and/or nitrene intermediates is proposed <86JCS(P1)1379>. [Pg.115]


See other pages where 1,2,3-Triazoles, 1,5-diamino is mentioned: [Pg.190]    [Pg.187]    [Pg.256]    [Pg.130]    [Pg.131]    [Pg.453]    [Pg.135]    [Pg.177]    [Pg.183]    [Pg.55]    [Pg.281]    [Pg.877]    [Pg.170]    [Pg.349]    [Pg.402]    [Pg.45]    [Pg.107]   
See also in sourсe #XX -- [ Pg.53 , Pg.117 ]




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3.5- Diamino-1,2.4-triazole

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