Progress in C—H Bond Functionalization on C-3 Position of Imidazo[1,2-a] pyridines

Selective C-5 Oxidative Radical Silylation of Imidazopyridines Promoted by Lewis Acid

“…Imidazo­[1,2- a ]­pyridine represents a promising building block with pharmaceutical applications; therefore, the functionalization of this heterocycle has been attracting considerable interest in the last two decades . Many reports focused on the C-3 functionalization of imidazo­[1,2- a ]­pyridines via the electrophilic or radical substitution, based on the electron-rich feature of this position . Only a few works concerned the C-5 substitution, e.g., hydroxyalkylation and alkylation via CDC processes.…”

Electrochemical Decarboxylative Coupling of N‐Substituted Glycines under Air: Access to C3‐Aminomethylated Imidazo[1,2‐a]pyridines

“…To date, a lot of methodologies have been achieved to decorate the representative core structure of 2-aryl imidazo [1,2-a]pyridines at different positions, especially, C3 and C2' ones (Scheme 1). [3] Apart from transition metals, light, or oxidants involved approaches, electrochemistry proved to be a green and practical alternative approach to expand the chemical space of imidazo[1,2-a]pyridine derivative by the process of losing or gaining electrons on the surface of electrodes. [3d,f] In the manner of electrochemical oxidation, except for the self-coupling examples, [4] a variety of reagents including thiols, [5] diselenides, [6] diaryl amine, [7] imidazoles, [8] trialkyl phosphite, [9] sodium halides, [10] thiocyanates, [11] carboxylic acids, [12] and aryl sulfinates [13] have been successfully applied to the oxidative cross-coupling of imidazo [1,2-a]pyridines at the C3 position.…”

Recent Advances in the α-C(sp3)-H Bond Functionalization of Glycine Derivatives

“…氮稠环化合物, 在医药和材料等领域具有广泛的应用价 值 [54] . C-3 位 C-H 官能团化是构建 3-取代咪唑并[1,2-a] 吡啶类化合物的简洁有效的方法 [55] . 2017 年, Tang 课题 组 [56] 在 2017 年, Chandrasekharam 课题组 [57] 极大关注 [59] .…”