39573-72-3

Usage

Synthesis Reference(s)

Tetrahedron, 50, p. 12113, 1994 DOI: 10.1016/S0040-4020(01)89564-8

Upstream product

• 61-82-5 3⁽⁵⁾-amino-1,2,4-triazole 
• 68-12-2 N,N-dimethyl-formamide 
• 98-86-2 acetophenone 
• 61-82-5 3-amino-1,2,4-triazole 
• 1201-93-0 1-phenyl-3-dimethylaminoprop-2-enone 
• 275-02-5 1-deaza-5-azapurine 
• 591-50-4 iodobenzene 
• 108-86-1 bromobenzene 
• 100-52-7 benzaldehyde 
• 121-44-8 triethylamine 
• 1010796-72-1 2-dimethylaminomethylene-4,4,4-trifluoro-1-phenylbutane-1,3-dione 

Downstream Products

• 118787-61-4 5,7-diphenyl-1,2,4-triazolo-[1,5-α]-pyrimidine 
• 118787-62-5 7-phenyl-5-(4-methoxyphenyl)-[1,2,4]triazolo[1,5-a]pyrimidine 

Relevant academic research and scientific papers

Regioselective Synthesis of 5-(Trifluoromethyl)[1,2,4]triazolo[1,5- a ]pyrimidines from β-Enamino Diketones

The use of β-enamino diketones as an easy entry to the regioselective synthesis of [1,2,4]triazolo[1,5- a ]pyrimidines is reported. These ketones reacted with 3-amino-1 H -1,2,4-triazoles to furnish exclusively 6-substituted 5-(trifluoromethyl)[1,2,4]tria

Vinylation of α-Aminoazoles with Triethylamine: A General Strategy to Construct Azolo[1,5-a]pyrimidines with a Nonsubstituted Ethylidene Fragment

A new general synthesis of pharmaceutically important azolo[1,5-a]pyrimidines starting from widely available 3(5)-aminoazoles, aldehydes, and triethylamine is developed. The key is to enable the vinylation reaction that allows the in situ generation of elusive acyclic enamines and the subsequent annulation reaction to occur. This direct and practical strategy is capable of constructing a range of 5,6-unsubstituted pyrazolo[1,5-a]pyrimidines and [1,2,4]triazolo[1,5-a]pyrimidines. More importantly, this protocol provides a concise synthetic route to prepare the clinically used zaleplon.

Synthesis method of [1, 2, 4] triazolo [1, 5-a] pyrimidine compound

The invention discloses a synthesis method of a [1, 2, 4] triazolo [1, 5-a] pyrimidine compound, and belongs to the technical field of organic synthesis. According to the technical scheme, the preparation method is characterized by comprising the following steps: dissolving an aldehyde compound, a 3-amino-1, 2, 4-triazole compound and triethylamine in a solvent toluene, then adding ammonium iodide and di-tert-butyl peroxide, and then reacting at 130 DEG C to prepare the target product [1, 2, 4] triazole [1, 5-a] pyrimidine compound. The synthesis process is simple and efficient, the [1, 2, 4] triazolo [1, 5-a] pyrimidine compound is directly prepared in one step through the one-pot cascade reaction without transition metal catalysis, the synthesis process is convenient to operate, the raw materials are simple, the reaction conditions are mild, the yield is high, the method has a very good application prospect, and meanwhile, the production cost is greatly reduced by taking triethylamine as the raw material.

Synthesis of New [1,2,4]Triazolo[1,5-a]pyrimidine Derivatives: Reactivity of 3-Amino[1,2,4]triazole towards Enaminonitriles and Enaminones

A diversity of new 7-substituted[1,2,4]triazolo[1,5-a]pyrimidine and 6-substituted[1,2,4]triazolo[1,5-a]pyrimidine-7-amine derivatives has been synthesized via reaction of 3-amino-[1,2,4]triazole with enaminonitriles and enaminones. The regio orientation and the structure of the products were confirmed by spectral and analytical data and synthesis via an alternative route. The procedure proved to be simple, efficient, and high yielding, and diversities of [1,2,4]triazolo[1,5-a]pyrimidines were obtained.

Direct (het)arylation of [1,2,4]triazolo[1,5-a]pyrimidines: Both eliminative and oxidative pathways

(Hetero)arylation of [1,2,4]triazolo[1,5-a]pyrimidine through the direct nucleophilic C[sbnd]H functionalization of the C-7 and C-5 positions has been implemented. The regioselective addition of a (het)aryl magnesium bromide to C-7 of 6-bromo-[1,2,4]triazolo[1,5-a]pyrimidine, followed by eliminative aromatization of the intermediate σH-adducts, has afforded 7-(hetero)aryl-substituted [1,2,4]triazolo[1,5-a]pyrimidines (the SNH reaction, proceeding according to the “addition-elimination” scheme). A second treatment with a Grignard reagent has resulted in the C-5 σH-adducts, which have been oxidized while being N-magnesium salts into [1,2,4]triazolo[1,5-a]pyrimidines, bearing various combinations of (hetero)aromatic substituents at C-5 and C-7 (the SNH process, realizing via the “addition-oxidation” scheme). As a result of optical and electrochemical studies, the obtained compounds have proved to be promising luminescent dyes and push-pull systems.

Molecular Engineering of Mechanochromic Materials by Programmed C-H Arylation: Making a Counterpoint in the Chromism Trend

The development of facile methods for screening organic functional molecules through C-H bond activation is a revolutionary trend in materials research. The prediction of mechanochromism as well as mechanochromic trends of luminogens is an appealing yet challenging puzzle. Here, we present a strategy for the design of mechanochromic luminogens based on the dipole moment of donor-acceptor molecules. For this purpose, a highly efficient route to 2,7-diaryl-[1,2,4]triazolo[1,5-a]pyrimidines (2,7-diaryl-TAPs) has been established through programmed C-H arylation, which unlocks a great opportunity to rapidly assemble a library of fluorophores for the discovery of mechanochromic regularity. Molecular dipole moment can be employed to explain and further predict the mechanochromic trends. The 2,7-diaryl-TAPs with electron-donating groups on the 2-aryl and electron-withdrawing groups on the 7-aryl possess a relatively small dipole moment and exhibit a red-shifted mechanochromism. When the two aryls are interchanged, the resulting luminogens have a relatively large dipole moment and display a blue-shifted mechanochromism. Seven pairs of isomers with opposite mechanochromic trends are presented as illustrative examples. The aryl-interchanged congeners with a bidirectional emission shift are structurally similar, which provides an avenue for understanding in-depth the mechanochromic mechanism.

Ultrasound irradiation promotes the synthesis of new 1,2,4-triazolo[1,5-a] pyrimidine

Ultrasonic irradiation was used in the synthesis of a series of novel 1,2,4-triazolo[1,5-a]pyrimidines. The products were synthetized from the cyclocondensation reaction of 1,1,1-trifluoro-4-metoxy-3-alken-2-one [CF 3C(O)CHC(R)OMe, where R = Ph, 4-F-C6H4, 4-Br-C6H4, 4-I-C6H4, 4-CH 3-C6H4, 4-CH3O-C6H 4, Thien-2-yl, Biphen-4-yl] or β-enaminones [RC(O)CHCHNMe 2, where R = Ph, 4-F-C6H4, 4-Br-C 6H4, 4-I-C6H4, 4-CH 3-C6H4, 4-CH3O-C6H 4, 4-NO2-C6H4, Thien-2-yl, Biphen-4-yl, Naphth-2-yl, Pyrrol-2-yl, CCl3] with 5-amino-1,2,4-triazole in acetic acid at 99 C with 5-17 min of ultrasound irradiation. This methodology has shown several advantages, such as shorter reaction times, mild conditions, high regioselectivity, and excellent yields, when compared with conventional thermal heating (oil bath).

The application of unsymmetrical vinylogous iminium salts and related synthons to the preparation of monosubstituted triazolo[1,5-a]pyrimidines

The reaction of vinylogous iminium salts and related analogs with 3-amino-1,2,4-triazole to yield 7-substituted and 5-substituted triazolo[1,5-a]pyrimidines is described.

(Substituted-phenyl)-1,2,4-triazolo[4,3-a]-pyrimidines and (substituted-phenyl)-1,2,4-triazolo[1,5-a]pyrimidines

This disclosure describes substituted 1,2,4-triazolo[1,5-a]pyrimidines and substituted 1,2,4-triazolo[4,3-a]pyrimidines which possess anxiolytic activity.