One-pot synthesis of [1,2,4]Triazolo[1,5-a]pyridines from azines and benzylidenemalononitriles via copper-catalyzed tandem cyclization

Lv, Jianguang; He, Zhiqing; Zhang, Jianmin; Guo, Yuwei; Han, Ziwei; Bao, Xinhua

doi:10.1016/j.tet.2018.06.002

Cited by 16 publications

(14 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, chemical shifts of C(2) in all synthesized compounds lay between 158 and 169 ppm which is common for triazolo[1,5‐a]pyridines,,, while C(3) of isomeric triazolo[4,3‐a]pyridines have chemical shifts about 130–140 ppm ,,…”

Section: Resultsmentioning

confidence: 96%

See 1 more Smart Citation

Synthesis of N‐Bridged 6,8‐Dinitrotriazolo[1,5‐a]pyridines

et al. 2019

View full text Add to dashboard Cite

Facile and efficient protocols for the synthesis of 2- R-6,8-dinitro [1,2,4]triazolo[1,5-a]pyridines from commercially available starting materials have been developed. The reactions proceed via cyclization of corresponding 3,5-dinitropyridine-2-yl hydrazides or aldehyde 3,5-dinitropyridine-2-yl hydrazones followed by in situ Dimroth rearrangement to provide these triazole fused bicyclic heterocycles in good yields under mild conditions. Another synthetic route to target N-bridged dinitro [1,2,4] triazolo [1,5-a]pyridines includes arylation of 5-aryltetrazoles with 2-chloro-3,5-dinitropyridine and subsequent thermal decomposition/cyclization.

show abstract

Section: Resultsmentioning

confidence: 96%

“…Triazole derivatives were also used as precursors for triazolo[1,5‐a]pyridines, Scheme , routes (d) and (e) . Finally, triazolo[1,5‐a]pyridines can be synthesized from acyclic starting materials (Scheme , route (f)) …”

Section: Introductionmentioning

confidence: 99%

Synthesis of N‐Bridged 6,8‐Dinitrotriazolo[1,5‐a]pyridines

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Encouraged by these results, we next moved to screen the azine substrates for the given reaction (Table ). Azine derivatives ( 1a–1l ) were prepared according to the previously reported procedures. − The amidation conditions were compatible with various functional groups such as fluoro, chloro, bromo, and trifluoro (Table , entries 3ca–3fa ). Electronic variation of substituents on the para positions of the phenyl rings did not have much influence on the reaction efficiency (Table , entries 3ba and 3ga ).…”

Section: Resultsmentioning

confidence: 99%

“…The synthesis of aromatic azines 1a–1l was done according to the previously reported procedures; their spectral characterization and other physical data matched those reported previously. − Hydrazine hydrate (1.0 g, 10 mmol, 50%) was added to a solution of acetophenone (1.2 g, 10 mmol) and AcOH (60.0 mg, 1.0 mmol) in EtOH (10 mL), and then the mixture was heated in a preheated oil bath to 100 °C with stirring and refluxed for 10 h. After cooling to room temperature, the mixture was filtered, washed with EtOH (20 mL × 4), and dried under vacuum. A yellow solid (1 E ,2 E )-1,2-bis(1-phenylethylidene)hydrazine 1a was obtained in 87% yield.…”

Section: Methodsmentioning

confidence: 99%

Rhodium-Catalyzed C(sp²)–H Amidation of Azine with Sulfonamides

Yong

Chen

et al. 2020

J. Org. Chem.

View full text Add to dashboard Cite

Direct C−H amidation of azine with sulfonamide was developed for the first time. The reactions proceeded smoothly under benign conditions and gave the corresponding products with high selectivity. This approach shows high regioselectivity, wide substrate scope, and functional group tolerance. Additionally, this transformation can also be scaled up to the gram level. This strategy allows for the direct preparation of ortho-sulfonamide-substituted ketone products, thus providing a good complement to previous C−H amidation.

show abstract

“…lononitriles, via copper-catalyzed tandem cyclization, gave Condensation of a 2:1 mixture of 2-oxo-N'-arylpropanehy-1,2,4-triazolo [1,5-a]pyridines. [9] Azines exhibit various drazonoyl chlorides 1 and phosphonic dihydrazide (2) in [10] and act as antitumor, [11] antipharmacological activities boiling ethanol for 3 h gave bis(N'-arylpropanehydrazonoyl convulsant, [12] [13] and antimicrobial [14] antioxidant, agents.…”

Section: Resultsmentioning

confidence: 99%

Facile, mild and efficient synthesis of azines using phosphonic dihydrazide

Khidre

Mohamed

Kariuki

et al. 2019

Phosphorus, Sulfur, and Silicon and the Related Elements

View full text Add to dashboard Cite

Several bis(N'-arylpropanehydrazonoyl chlorides) were synthesized in good yields from condensation reactions of hydrazonoyl chlorides and phosphonic dihydrazide. Under the conditions employed, none of the expected phosphorylhydrazines were isolated. Nucleophilic substitution of bis(N'arylpropanehydrazonoyl chlorides) with thiophenol, sodium phenylsulfinate, hydroxyl amine, and piperidine afforded the corresponding azines. Similarly, 1,2-bis(heteroaryl)ethylidene)hydra-zines were produced from reaction of phosphonic dihydrazide and heteroaryl methyl ketones. The structures of the products were confirmed by NMR and IR spectral data along with X-ray crystal structure determination and their purities were confirmed by the elemental analyses.

show abstract

One-pot synthesis of [1,2,4]Triazolo[1,5-a]pyridines from azines and benzylidenemalononitriles via copper-catalyzed tandem cyclization

Cited by 16 publications

References 69 publications

Synthesis of N‐Bridged 6,8‐Dinitrotriazolo[1,5‐a]pyridines

Synthesis of N‐Bridged 6,8‐Dinitrotriazolo[1,5‐a]pyridines

Rhodium-Catalyzed C(sp²)–H Amidation of Azine with Sulfonamides

Facile, mild and efficient synthesis of azines using phosphonic dihydrazide

Contact Info

Product

Resources

About

One-pot synthesis of [1,2,4]Triazolo[1,5-a]pyridines from azines and benzylidenemalononitriles via copper-catalyzed tandem cyclization

Cited by 16 publications

References 69 publications

Synthesis of N‐Bridged 6,8‐Dinitrotriazolo[1,5‐a]pyridines

Synthesis of N‐Bridged 6,8‐Dinitrotriazolo[1,5‐a]pyridines

Rhodium-Catalyzed C(sp2)–H Amidation of Azine with Sulfonamides

Facile, mild and efficient synthesis of azines using phosphonic dihydrazide

Contact Info

Product

Resources

About

Rhodium-Catalyzed C(sp²)–H Amidation of Azine with Sulfonamides