Copper-catalyzed intramolecular dehydrogenative cyclization: direct access to sensitive formyl-substituted imidazo[1,2-a]pyridines
作者:Li-Hai Zhai、Li-Hong Guo、Bai-Wang Sun
DOI:10.1039/c5ra19085a
日期:——
A direct method for the synthesis of formyl-substituted imidazo[1,2-a]pyridines was achieved easily from cyclization of aminopyridines and cinnamaldehydes via copper catalysis. This oxidative cyclization process involved direct C–H bond functionalization, and C–C/C–N bond formation. In this transformation, the sensitive aldehyde group was preserved under oxidative conditions.
通过铜催化氨基吡啶和肉桂醛的环化,很容易实现直接合成甲酰基取代的咪唑并[1,2- a ]吡啶的直接方法。这种氧化环化过程涉及直接的C–H键功能化和C–C / C–N键形成。在该转化中,敏感的醛基在氧化条件下得以保留。
Ru(II)-Catalyzed Synthesis of Fused Imidazo[1,2-<i>a</i>]pyridine-chromenones and Methylene-Tethered Bis-imidazo[1,2-<i>a</i>]pyridines and Regioselective O-Acetoxylation of Imidazo[1,2-<i>a</i>]pyridines
作者:Javeed Ahmad Tali、Ravi Shankar
DOI:10.1021/acs.orglett.3c00578
日期:2023.5.12
unprecedented protocol via ruthenium-catalyzed annulation for the synthesis of 6H-chromeno[4′,3′:4,5]imidazo[1,2-a]pyridin-6-one, and functionalized 2-(3-formylimidazo[1,2-a]pyridin-2-yl)phenyl acetate has been revealed by intramolecular chelation-assisted C–H activation. Additionally, a one-pot approach for creating bis(2-phenylimidazo[1,2-a]pyridin-3-yl)methane (BIP) has been realized through ruthenium
在此,我们公开了一种前所未有的通过钌催化环化合成 6 H -chromeno[4',3':4,5]imidazo[1,2- a ]pyridin-6-one 和功能化 2-(已通过分子内螯合辅助的 C-H 活化揭示了3-甲酰咪唑并 [1,2- a ] 吡啶-2-基) 乙酸苯酯。此外,通过使用甲酸的钌催化,已经实现了用于产生双(2-苯基咪唑并[1,2- a ]吡啶-3-基)甲烷(BIP)的一锅法。该方法用于 BIP 的克级合成和已上市药物佐利米丁的经济步骤后期功能化,收率良好。
K<sub>2</sub>S<sub>2</sub>O<sub>8</sub>‐Mediated C‐3 Formylation of Imidazopyridines Using Glyoxylic Acid
作者:Harish K. Indurthi、Samarpita Das、Pallavi Saha、Deepak K. Sharma
DOI:10.1002/ejoc.202300829
日期:2023.12
A metal-free formylation of imidazopyridines with K2S2O8 by direct decarboxylative cross-coupling of glyoxylic acid is described. This reaction features broad substrate scope, good functional group tolerance, and generate products in good yields.
描述了通过乙醛酸的直接脱羧交叉偶联用K 2 S 2 O 8进行咪唑并吡啶的无金属甲酰化。该反应底物范围广,官能团耐受性好,产物收率高。
Facile synthesis of new imidazo[1,2-a]pyridines carrying 1,2,3-triazoles via click chemistry and their antiepileptic studies
The present article reports the synthesis and anticonvulsant studies of new 2-arylimidazo[1,2-a]pyridines carrying suitably substituted 1,2,3-triazoles as well as their intermediates. The structures of newly synthesized compounds were confirmed by various spectroscopic techniques. The anticonvulsant study was carried out by MES and scPTZ screening methods, while their toxicity study was performed following Rotarod method. The active compounds showed enhanced seizure control in scPTZ method when compared with that of MES method. Compounds 3f, 4c, 4f, 5k, 5p and 5w carrying active pharmacophores exhibited complete protection against seizure and their results were comparable with standard drug diazepam. Majority of new compounds were found to be non-toxic, while few of them showed toxicity at 100 mg/kg. The c log P values of target compounds are in the range of 3.5-5.3, which confirm their lipophilic nature. (C) 2013 Elsevier Ltd. All rights reserved.