An alternative approach to the synthesis of [1,2,4]triazolo[1,5‐a]pyridine‐8‐carbonitriles, their crystal structure, and DFT calculations

Abstract

New representatives of [1,2,4]triazolo [1,5-a]pyridine-8-carbonitriles were synthesized via the condensation of β-diketones or β-dialdehydes and characterized using MS spectrometry, 1 H, 13 C and, 19 F NMR and IR spectroscopy. Crystal structures of two compounds were established using X-ray analysis and showed that title compounds are prone to the formation of planar molecules. The absence of band responsible for CN stretching vibration in trifluoromethylcontaining compounds was explained using the DFT calculations method, which also showed a significant influence of fluorines introducing on the energy gap between HOMO and LUMO.

Correction to “Regioselective Synthesis of Highly Functionalized Pyrazoles from N-Tosylhydrazones”

“…To confirm the correct structure of our previous reported compounds, we obtained the single-crystal X-ray analysis of 2aa′ , and the 1,2,4-triazole motif was confirmed. Meanwhile, the NMR data of 2b′ were in agreement with the literature values . The real structure of 2b′ and 2aa′ was shown in Figure .…”

“…Meanwhile, the NMR data of 2b′ were in agreement with the literature values. 2 The real structure of 2b′ and 2aa′ was shown in Figure 1.…”

Synthesis and Antibacterial Activity of Novel Triazolo[4,3-a]pyrazine Derivatives

“…Various antimicrobial triazole derivatives have Molecules 2023, 28, 7876 2 of 16 been developed and most of them show potent antimicrobial activity [8]. It is particularly noteworthy that more effective antibacterial candidates might be obtained from the various triazole fused heterocyclic derivatives, extensively existing in chemistry, such as triazolo[1,5-a]pyrimidine [9], triazolo [4,5-c]pyridine [10], triazolo [4,3-a]pyrazine [11], triazolo [4,5-d]pyrimidine [12], triazolo [4,3-a]quinoxaline [13], triazolo[1,5-a]quinolines [14], and triazolo[1,5-a]pyridine [15,16]. Some triazole fused heterocyclic derivatives have been found to have high antibacterial activity against both drug-sensitive and drug-resistant pathogens and are not inferior to the first-line antimicrobial agents [17,18].…”

Expanding the chemical space of 3(5)-functionalized 1,2,4-triazoles

“…Ethyl 5-(cyanomethyl)-1 H -1,2,4-triazole-3-carboxylate (1g) was synthesized from compound 5g (2.48 g). Yield 2.84 g (63%), yellow powder, mp 111–112°C (mp 111–112°C 50 ). Physical and spectral data were in accordance with the previously reported.…”