31592-08-2

Upstream product

• 61-82-5 3⁽⁵⁾-amino-1,2,4-triazole 
• 1117-37-9 ethyl (E)-3-(dimethylamino)acrylate 
• 64-18-6 formic acid 
• 32084-27-8 2-hydrazino-4(3H)-one-pyrimidine 
• 617-48-1 malic acid 
• 110-86-1 pyridine 
• 3674-13-3 2,3-dibromopropionic acid ethyl ester 

Downstream Products

• 52341-91-0 7-chloro-[1,2,4]triazolo[1,5-a]pyrimidine 
• 275-02-5 1-deaza-5-azapurine 

Relevant academic research and scientific papers

Studies with functionally substituted enamines: The reactivity of enaminals and enamino esters toward naphthoquinone, hydrazonoyl halides, aminoazoles and hippuric acid

Whereas enamines 1a,b react with naphthoquinone (2) to yield the naphthofuranals 5a,b, enamine ester 1c react with 2 to yield benzoindole derivatives 7. Enamine 1b reacts with hydrazonoyl halides 8 to yield 3,4-disubstituted pyrazoles 12. On the other hand, the enaminal 1a failed to react with 8, while enamine ester 1c afforded hydrazone 16 on treatment with 8. The enamino ester 1b afforded triethyl 1,3,5-benzenetricarboxylates on refluxing in acetic acid. Georg Thieme Verlag Stuttgart.

5-oxo and 7-oxo derivatives of [1,2,4]triazolo-[1,5-a]pyrimidine: Characterization and theoretical study

4,5-Dihydro-5-oxo-[1,2,4]triazolo-[1,5-a]pyrimidine (5HtpO) and 4,7- dihydro-7-oxo-[1,2,4]triazolo-[1,5-a]pyrimidine (7HtpO) have been synthesized by the condensation of 3-amino-[1,2,4]triazole with a reagent bearing the three carbon atoms that close the six-membered ring in a strongly acidic (7HtpO) or strongly basic (5HtpO) medium. The crystal structures of these compounds have been determined by X-ray diffraction, exhibiting the N4-H tautomer, as expected from the RHF/AMI calculations. The different possibilities for binding metal ions are discussed from the MO results. (C) 2000 Elsevier Science B.V.

Preparation and pyrolysis of 1-(pyrazol-5-yl)-1,2,3-triazoles and related compounds

1-(Pyrazol-5-yl)-1,2,3-triazoles 8a, 9a and 10 are prepared by cycloaddition of 5-azidopyrazoles with methyl prop-2-ynoate. The regiochemistry of the process is confirmed by synthesis of 9a using an authentic route from ethyl 2-formyl-2-diazoacetate 13. Flash vacuum pyrolysis of 8a, 9a and 10 gives 5-methoxypyrazolo[1,5-a]pyrimidin-7-ones 16-18 by a mechanism involving an unexpected oxoketenimineimidoyl ketene rearrangement as the key step. The mechanism is supported by a 13C labelling experiment. A general route to pyrazolo[1,5-a]pyrimidin-7-ones from pyrazolylaminomethylene Meldrum's acid derivatives (e.g. 30-32) is also reported.