Article
Chemistry, Organic
Pei He, Chunbo Liu, Qinpeng Shen, Jianjun Xia, Ying Han, Wen Xiong, Zhenjie Li, Shiyun Tang, Zhihua Liu, Fengmei Zhang
Summary: A bromination reaction of hydrocarbons with CBr4 as a bromine source, promoted by NaOH, has been developed. The reaction method shows high efficiency and regioselectivity for the synthesis of C3-brominated imidazo[1,2-alpha]pyridines. This method serves as an effective and simple approach for C-X bond construction, providing a supplement to the halide of imidazo[1,2-alpha]pyridines.
LETTERS IN ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Hongmei Jiang, Haicheng Shen, Sha Zhu, Binbin Wang, Yujie Yang, Zhibin Nong, Min Yi, Shiyun Tang, Qing-Wen Gui
Summary: A novel and inexpensive double thiolation reagent has been reported for sulfurizing a broad range of imidazo[1,2-alpha]pyridines under mild conditions. Diethylaminosulfur trifluoride, a common nucleophilic fluorinating reagent, was utilized as the novel thiolation reagent in this study.
Review
Chemistry, Multidisciplinary
Saradindu Debnath, Syaleena Parveen, Priyankar Pradhan, Ipsita Das, Tapas Das
Summary: Nitrogen heterocycles are vital compounds found in nature or synthesized, playing essential roles in living systems and having potential applications in drugs and materials.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Organic
Yong Yuan, Zhilin Zhou, Lin Zhang, Liang-Sen Li, Aiwen Lei
Summary: The electrochemical oxidative C3 acyloxylation of imidazo[1,2-alpha]pyridines was demonstrated for the first time, showing that it can be carried out under mild conditions and is applicable to alkyl carboxylic acids as well as aromatic carboxylic acids.
Article
Chemistry, Organic
Javeed Ahmad Tali, Ravi Shankar
Summary: Here, we report an unprecedented protocol using ruthenium-catalyzed annulation for the synthesis of 6H-chromeno[4 ',3 ':4,5]imidazo[1,2-a]pyridin-6-one, and a new method for intramolecular chelation-assisted C-H activation to produce functionalized 2-(3-formylimidazo[1,2-a]pyridin-2-yl)phenyl acetate. Furthermore, a one-pot approach using ruthenium catalysis and formic acid has been developed for the gram-scale synthesis of bis(2-phenylimidazo[1,2-a]pyridin-3yl)methane (BIP) and the late-stage functionalization of zolimidine, a marketed drug, with good yield.
Article
Chemistry, Organic
Xianyan Liu, Xin Guo, Zhibo Jiang, Chonglong Li, Zedong Nan, Yafeng Liu
Summary: This study explores the photocatalyzed intermolecular C-N bond formation of 2-aminopyridines with ketones using NH4I as the catalyst, resulting in the synthesis of imidazo[1,2-a]pyridines under milder conditions. The reaction can be induced by sunlight and is applicable for 2-aminopyridines, ketones, and sulfide derivatives, as well as 2-aminopyridines and sulfoxonium ylide.
TETRAHEDRON LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Hua Yang, Ning Huang, Nengqing Wang, Haicheng Shen, Fan Teng, Xiaoying Liu, Hongmei Jiang, Mei-Chen Tan, Qing-Wen Gui
Summary: The novel method described in this study achieves regioselective iodination of imidazo[1,2-alpha]pyridines at their C3 position without the need for metal catalysts, using ultrasound acceleration and a green alcohol solvent. This approach significantly improves reaction efficiency and rate compared to conventional heating systems, maximizing the iodine atom economy.
Article
Chemistry, Organic
Dhananjay S. Nipate, Sonam Jaspal, Vikki N. Shinde, Krishnan Rangan, Anil Kumar
Summary: A metal-free method for hydroxyfluoroalkylation of indoles and imidazo[1,2-a]pyridines has been developed via TEMPO-mediated C(sp(3))-H and C(sp(2))-H bond cross-dehydrogenative coupling of fluorinated alcohols. The protocol showed good yields, broad substrate scope, and scalability, with mechanistic investigation suggesting involvement of a radical pathway.
Article
Chemistry, Multidisciplinary
Sifeng Li, Taimin Wang, Xingchen Li, Lijing Fang, Hongbin Zhai, Bin Cheng
Summary: A switchable electrochemical approach has been developed for the C3-aminomethylation and C3-arylmethylation of imidazo[1,2-a]pyridines, showing remarkable regio- and chemoselectivities under environmentally benign conditions, and potential for late-stage derivatization of natural products and drugs using N-methyl amines.
Article
Chemistry, Organic
Javeed Ahmad Tali, Gulshan Kumar, Davinder Singh, Ravi Shankar
Summary: This study presents an efficient Pd(II)-catalyzed selective C8 alkenylation of imidazo[1,2-a]pyridines using electronically biased olefinic substrates. Selective mono-alkenylation was achieved through N-chelation overriding O-chelation at four available C-H sites, enabling late-stage functionalization of the marketed drug zolimidine with high C8 regioselectivity. Various substituted heteroaryl alkenes can be obtained with moderate to good yields.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Jingyun Zhu, Ziyue Chen, Meng He, Daoxin Wang, Liangsen Li, Junchao Qi, Renyi Shi, Aiwen Lei
Summary: The study developed an efficient and metal-free synthesis method for the production of biologically and synthetically useful compounds. The reaction exhibited high yields, and the scaled-up experiment resulted in an ideal yield of the desired product.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Organic
Frederic Vuillermet, Joanick Bourret, Guillaume Pelletier
Summary: The study describes a new method for the synthesis of imidazo[1,2-a]pyridines through the reaction between 2-chloropyridines and 2H-azirines, which involves the formation of electrophilic trifloyl-aziridin-2-yl triflate species and transient pyridinium salts. Thorough optimization of the activation/cyclization process resulted in selective formation of C3-substituted imidazo[1,2-a]pyridines with yields ranging from 15% to 85% for a variety of substituted heterocycles.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Review
Chemistry, Organic
Javeed Ahmad Tali, Gulshan Kumar, Bhupesh Kumar Sharma, Younis Rasool, Yashika Sharma, Ravi Shankar
Summary: Imidazo[1,2-a]pyridine has potent medicinal properties and has attracted much interest in drug development. This review provides an overview of the outcomes obtained in the field of global ring functionalization, focusing on the functionalization reactions at each carbon atom.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Review
Chemistry, Organic
Javeed Ahmad Tali, Gulshan Kumar, Bhupesh Kumar Sharma, Younis Rasool, Yashika Sharma, Ravi Shankar
Summary: Imidazo[1,2-a]pyridine has potent medicinal properties, making the discovery of novel synthesis and functionalization methods an exciting area of research.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
Chun-Hua Ma, Ming Chen, Zhi-Wen Feng, Yan Zhang, Jin Wang, Yu-Qin Jiang, Bing Yu
Summary: This review summarizes recent advances in radical reactions for the direct functionalization of imidazo[1,2-a]pyridines through transition metal catalysis, metal-free oxidation, and photocatalysis strategies.
NEW JOURNAL OF CHEMISTRY
(2021)
