在温和的电解条件下已开发出无试剂的分子内脱氢C–N交叉偶联反应。在这种原子经济和一步经济的一锅法中,有价值的1,2,4-三唑并[4,3- a ]吡啶和相关的杂环化合物可以从可商购的脂族或(杂)芳族醛和2-肼基吡啶。各种官能团都与这种无金属和无氧化剂的方案兼容,可以轻松地以克为单位进行操作。这种新方法被应用于最畅销药物Xanax的合成和后期功能化,以在生物学相关的先导分子中产生化学多样性。
Palladium-Catalyzed Triazolopyridine Synthesis: Synthesis of 7-Chloro-3-(2-Chlorophenyl)-1,2,4-Triazolo[4,3-a]Pyridine
摘要:
Chloramine-T is thermally unstable and heating of chloramines-T beyond the temperature disclosed in this procedure should not be conducted without further safety evaluation. Hydrazine should be handled in a fume hood as it is an animal carcinogen and has been identified it as a potential human carcinogen. In addition, anhydrous hydrazine is potentially explosive, especially in contact with metals, and should only be handled as its hydrate.
Palladium-Catalyzed Coupling of Aldehyde-Derived Hydrazones: Practical Synthesis of Triazolopyridines and Related Heterocycles
作者:Oliver R. Thiel、Michal M. Achmatowicz、Andreas Reichelt、Robert D. Larsen
DOI:10.1002/anie.201001999
日期:2010.11.2
The palladium‐catalyzed intermolecular coupling of aldehyde‐derived hydrazones with chloroazines, followed by oxidative cyclization under mild conditions afforded access to a broad variety of bicyclic heterocyclic scaffolds (see scheme) that have potential for use in drug discovery.
Product and Mechanism of Gas-phase Pyrolysis of 2-arylidinehydrazinopyrimidines: Interesting Route to Condensed Heterocycles[1]
作者:Sundus A. Al-Awadi、Maher R. Ibrahim、Osman M. E. El-Dusouqui、Nouria A. Al-Awadi
DOI:10.1002/jhet.2276
日期:2015.11
Gas‐phasepyrolysis of N‐arylidine‐N′‐pyrimidin‐2‐yl‐hydrazine derivatives 1a, 1b, 1c, 1d, 1e gave the corresponding arylnitriles 2a, 2b, 2c, 2d, 2e, 2‐aminopyrimidine 3, 3‐phenyl‐1,2,4‐triazolo[4,3‐a]pyrimidines 4, 2‐phenyl‐1,2,4‐triazolo[1,5‐a]pyrimidines 5, 2,4,5‐triphenyl‐1H‐imidazole 6, and 2,3‐diphenylquinoline 7. The analyses of the reaction products are reported and used to elucidate the mechanism
的气相热解Ñ -arylidine- N' -嘧啶-2-基-肼衍生物1A,1B,1C,1D,1E,得到相应的arylnitriles图2a,图2b,图2c,2d中,2E,2-氨基嘧啶3,3-苯基-1,2,4-三唑并[4,3一]嘧啶4,2-苯基-1,2,4-三唑并[1,5-一个]嘧啶5,2,4,5-三苯基-1- ħ咪唑6和2,3-二苯基喹啉7。报告了反应产物的分析,并用于阐明热解过程的机理。
RuCl3/Oxone: An efficient combination for the synthesis of 3-aryl-[1,2,4]triazolo[4,3-a]pyridines from 2-(2-arylidenehydrazinol)pyridines
作者:Tallapally Swamy、Padma Raviteja、Goskula Srikanth、Basi V. Subba Reddy、Vadde Ravinder
DOI:10.1016/j.tetlet.2016.10.110
日期:2016.12
An efficient and convenient method for the synthesis of 3-aryl[1,2,4]triazolo[4,3-a]pyridines has been developed involving RuCl3/Oxone oxidative cyclization of 2-(2-arylidenehydrazinyl)pyridines, which occurs chemoselectively at the pyridine nitrogen. RuCl3 can be used as an efficient homogeneous catalyst for the synthesis of triazolopyridines through a direct intramolecular cyclization involving CN
已经开发出一种有效且方便的合成3-芳基[1,2,4]三唑并[4,3- a ]吡啶的方法,该方法涉及RuCl 3 / Oxone对2-(2-亚芳基肼基嗪)吡啶的氧化环化反应。在吡啶氮上有化学选择性。RuCl 3可以用作通过涉及C N键形成的直接分子内环化合成三唑并吡啶的有效均相催化剂。