205655-15-8Relevant articles and documents
Use of imidazo[1,2-a]pyridine as a carbonyl surrogate in a mannich-like, catalyst free, one-pot reaction
Naresh, Gunaganti,Lakkaniga, Naga Rajiv,Kharbanda, Anupreet,Yan, Wei,Frett, Brendan,Li, Hong-Yu
, p. 770 - 777 (2019)
Derivatization of imidazo[1,2-a]pyridine scaffolds have gained considerable attention due to the biological significance of therapeutics based on the imidazopyridine core. By utilizing a catalyst-free, “Mannich type” reaction, we developed a simple and efficient protocol to aminomethylate the C-3 position of imidazo[1,2-a]pyridine through a multicomponent, de-carboxylation reaction involving imidazo[1,2-a]pyridine, a secondary amine, and glyoxylic acid. The developed protocol re-quires mild reaction conditions and furnishes diverse imid-azo[1,2-a]pyridine analogues from commercially available starting materials. Additionally, the current protocol improves prior methods, which were limited by the amine substrate scope. Taken together, this current methodology permits rapid diversification of imidazo[1,2-a]pyridines to enhance combinatorial efficiency in the drug discovery processes.
Catalyst free, C-3 functionalization of imidazo[1,2-a]pyridines to rapidly access new chemical space for drug discovery efforts
Gunaganti, Naresh,Kharbanda, Anupreet,Lakkaniga, Naga Rajiv,Zhang, Lingtian,Cooper, Rose,Li, Hong-yu,Frett, Brendan
, p. 12954 - 12957 (2018)
Multicomponent reactions (MCRs) are robust tools for the rapid synthesis of complex, small molecule libraries for use in drug discovery and development. By utilizing MCR chemistry, we developed a protocol to functionalize the C-3 position of imidazo[1,2-a
Solvent and catalyst-free synthesis of imidazo[1,2-a]pyridines by grindstone chemistry
Godugu, Kumar,Nallagondu, Chinna Gangi Reddy
, p. 250 - 259 (2020/10/23)
The present work describes the solvent and catalyst-free synthesis of imidazo[1,2-a]pyridines in excellent to nearly quantitative yields from 2-aminopyridines and a wide variety of ω-bromomethylketones using a grindstone procedure at 25°C to 30°C for 3 to
Regioselective C-H dithiocarbamation of indolizines with tetraalkylthiuram disulfide under metal-free conditions
Cao, Hua,Lin, Jiatong,Liu, Xiang,Song, Dan,Zhan, Haiying,Zhang, Zemin,Zhuang, Canzhan
supporting information, p. 5284 - 5288 (2021/06/28)
An efficient and straightforward metal-free regioselective C-H dithiocarbamation of indolizines with tetraalkylthiuram disulfide has been described. A series of indolizine-dithiocarbamate derivatives were easily accessed in moderate to good yields with a broad scope. In addition, imidazo[1,2-a]pyridines were also well tolerated to afford diverse imidazoheterocycle-dithiocarbamate products, which are expected to be utilized for drug discovery. Of note, the reaction could be readily scaled up, and shows its practical value in organic synthesis.
Metal-free, Tf2NH-catalyzed 1, 6-conjugate addition of imidazopyridine to para-quinone methides: Easy access to C3-functionalized triarylmethane imidazopyridine
Khonde, Nilesh S.,Said, Madhukar S.,Sabane, Jagjivan K.,Gajbhiye, Jayant M.,Kumar, Pradeep
supporting information, (2021/10/30)
An inexpensive and commercially available Tf2NH-catalyzed 1,6-conjugate addition of imidazopyridine (IMPY) heterocycles to para-quinone methides (p-QMs) is reported. The present transformation provides a diverse class of C3-functionalized triarylmethanes heterocyclic derivatives of imidazopyridine. These metal-free transformations provided a very broad substrate scope of conjugate addition product with a high yield up to 97% within a short duration.
Metal-free oxidative decarbonylative halogenation of fused imidazoles
Kumar, Gulshan,Shankar, Ravi,Singh, Davinder,Tali, Javeed Ahmad
supporting information, p. 20551 - 20555 (2021/11/23)
An efficient strategy has been developed for the deformylative halogenation of carbaldehyde imidazo-fused heterocycles in the presence of TBHP controlled by temperature. A convenient and sequential functionalization (C8 to C3) portrays the synthetic utility of the current method.N-Heterocycle benzamide products were also observedviathe ring opening of imidazopyridines through the cleavage of C-C bond at high temperatures. Features of this method include temperature-controlled excellent regioselectivity, mild conditions and functional group tolerance.
Microwave-assisted synthesis and luminescent activity of imidazo[1,2-a]pyridine derivatives
Rodríguez, Juan C.,Maldonado, Rony A.,Ramírez-García, Gonzalo,Díaz Cervantes, Erik,de la Cruz, Fabiola N.
, p. 2279 - 2287 (2020/03/16)
In this work, a series of phenacyl bromide derivatives was synthesized and employed as key intermediate for the synthesis of substituted imidazo[1,2-a]pyridines. First, phenacyl bromide molecules were obtained from the bromination reaction of acetophenones assisted by microwave irradiation, obtaining the products 4a-v in a 15 minutes reaction with yields in the range of 50% to 99%. Subsequently, the conjugation of these molecules with 2-aminopyridine conduced to the production of imidazo[1,2-a]pyridine derivatives (7a-v) in a 60-second reaction with yields of 24% to 99%. Improved yields were determined with respect to those obtained with more tedious methodologies like thermally and mechanically assisted routes. Intense luminescence emissions in the purple and blue regions of the electromagnetic spectra were observed under UV excitation according to the nature of the substituents. This environmentally friendly methodology is expected to constitute an important class of organic compounds for the development of biomarkers, photochemical sensors, and medicinal applications.
PhI(OAc)2-mediated oxidative C[sbnd]H sulfoximination of imidazopyridines under mild conditions
Luan, Nannan,Liu, Zhenwei,Han, Shuaijun,Shen, Linhua,Li, Jingya,Zou, Dapeng,Wu, Yangjie,Wu, Yusheng
supporting information, (2019/11/26)
A facile protocol for direct oxidative C[sbnd]N bond coupling of unactivated imidazo[1,2-a]pyridines with NH-sulfoximines was disclosed using sulfoximines as the nitrogen sources in the presence of (diacetoxy)iodobenzene (PhI(OAc)2). The reacti
Metal-Free Regioselective Alkylation of Imidazo[1,2- a ]pyridines with N -Hydroxyphthalimide Esters under Organic Photoredox Catalysis
Jin, Can,Sun, Bin,Xu, Min,Xu, Tengwei,Yang, Jin,Zhang, Liang,Zhu, Rui
supporting information, p. 363 - 368 (2020/02/27)
A visible-light-induced direct C-H alkylation of imidazo[1,2- a ]pyridines has been developed. It proceeds at room temperature by employing inexpensive Eosin Y as a photocatalyst and alkyl N -hydroxyphthalimide (NHP) esters as alkylation reagents. A varie
A simple and efficient route to 2-arylimidazo[1,2-a]pyridines and zolimidine using automated grindstone chemistry
Das, Dharmendra,Bhutia, Zigmee T.,Panjikar, Padmini C.,Chatterjee, Amrita,Banerjee, Mainak
supporting information, p. 4099 - 4107 (2020/09/09)
A green and efficient mechanochemical method for the synthesis of a series of 2-arylimidazo[1,2-a]pyridines was developed using an electrical grinder. I2 catalyzed mechanochemical grinding facilitates the cyclocondensation reaction between various aryl methyl ketones and 2-aminopyridines to afford 2-arylimidazo[1,2-a]pyridines in good yields at ambient temperature. The method was successfully used for the gram-scale synthesis of a marketed drug, zolimidine. The noticeable advantages of this environmentally sustainable protocol include mild conditions, simple instrumentation, inexpensive catalyst, atom economy, short reaction time etc.