419557-34-9

Upstream product

• 2142-68-9 1-(2-chlorophenyl)ethanone 
• 7147-44-6 1-(2-chlorophenyl)ethanone oxime 
• 504-29-0 2-aminopyridine 
• 896905-07-0 1-(2-chlorophenyl)ethanone O-acetyl oxime 
• 401514-40-7 1-chloro-2-(2,2-dibromovinyl)benzene 
• 5000-66-8 2-chlorophenacyl bromide 
• 110-86-1 pyridine 

Downstream Products

• 1609583-38-1 2-(2-chlorophenyl)-3-(phenylthio)imidazo[1,2-a]pyridine 

Relevant academic research and scientific papers

Oxidation Potential-Guided Electrochemical Radical-Radical Cross-Coupling Approaches to 3-Sulfonylated Imidazopyridines and Indolizines

Oxidation potential-guided electrochemical radical-radical cross-coupling reactions between N-heteroarenes and sodium sulfinates have been established. Thus, simple cyclic voltammetry measurement of substrates predicts the likelihood of successful radical-radical coupling reactions, allowing the simple and direct synthetic access to 3-sulfonylated imidazopyridines and indolizines. The developed electrochemical radical-radical cross-coupling reactions to sulfonylated N-heteroarenes boast the green synthetic nature of the reactions that are oxidant- and metal-free.

Microwave-assisted synthesis and luminescent activity of imidazo[1,2-a]pyridine derivatives

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.

CuCl2-catalyzed N[sbnd]O bond cleavage of oxime esters: Approach to imidazoheterocycles and furo[3,2-c]chromenyl fused imidazoles

An articulate approach to a diverse set of imidazoheterocycles in good to high yields via a copper-catalyzed aza-annulation of several oxime esters with a group of 2-amino-azaarenes was developed. The above cyclization reaction probably proceeds via a single electron transfer process which embodies a new technique for creating two new C[sbnd]N bonds for imidazole ring synthesis. Gratifyingly, the implementation of this chemistry could be further stretched to the synthesis of a novel class of fused imidazoles bearing a furo[3,2-c]chromene moiety via a sequential C[sbnd]N bond formation, followed by C(sp2)-H functionalization/5-endo-dig-oxacyclization (C[sbnd]C and C[sbnd]O bonds) of in situ produced fused imidazoles with cyclic enynones in the presence of copper(II) as a π-electrophilic Lewis acid catalyst.

Ultrasound-assisted synthesis of imidazo[1,2-a]pyridines an d sequential one-pot preparation of 3-selanyl-imidazo[1,2-a]pyridine derivatives

A simple and rapid method to synthesize imidazo[1,2-a]pyridines starting from 2-aminopyridine and 2-bromoacetophenone derivatives under ultrasonic irradiation was developed. This protocol tolerates a wide range of 2-bromoacetophenone derivatives to produce a variety of imidazo[1,2-a]pyridines in good to excellent yields. Additionally, the one-pot preparation of 3-(organylselanyl)imidazo[1,2-a]pyridines via a sequential method is presented. In this case, different diorganyl diselenides were used as starting materials to afford the corresponding coupling products in excellent yields and short reaction times under sonication. The reactions were conducted in PEG-400, a cheap and nontoxic solvent, compatible with the ultrasound conditions in an environmentally benign process.

Metal-Free Site-Specific Hydroxyalkylation of Imidazo[1,2- A[pyridines with Alcohols through Radical Reaction

An effective approach to realize the direct hydroxyalkylation of imidazo[1,2-a]pyridines with alcohols promoted by di-tert-butyl peroxide was described without any metal catalyst. It is the first time that the dehydrogenative C(sp3)-C(sp2) coupling of imidazo[1,2-a]pyridines with alcohols occurred regioselectively at the C-5 position of imidazo[1,2-a]pyridines. Multisubstituted imidazopyridine derivatives were smoothly synthesized in moderate to good yields. Through a series of control experiments, a free-radical pathway was proposed to explain the experiment.

Metal-Free Site-Specific Hydroxyalkylation of Imidazo[1,2- a]pyridines with Alcohols through Radical Reaction

An effective approach to realize the direct hydroxyalkylation of imidazo[1,2-a]pyridines with alcohols promoted by di-tert-butyl peroxide was described without any metal catalyst. It is the first time that the dehydrogenative C(sp3)-C(sp2) coupling of imidazo[1,2-a]pyridines with alcohols occurred regioselectively at the C-5 position of imidazo[1,2-a]pyridines. Multisubstituted imidazopyridine derivatives were smoothly synthesized in moderate to good yields. Through a series of control experiments, a free-radical pathway was proposed to explain the experiment.

Heterogeneously copper-catalyzed oxidative synthesis of imidazo[1,2-a]pyridines using 2-aminopyridines and ketones under ligand- and additive-free conditions

An efficient and mild heterogeneously CuCl2/nano-TiO 2-catalyzed aerobic synthesis of imidazo[1,2-a]pyridines from 2-aminopyridines and ketones has been developed using air as the oxidant in the absence of any ligands and additives. This strategy was compatible with a large range of substrates, including unactivated aryl ketones and unsaturated ketones and went through the C-H bond functionalization mechanism instead of I --assisted Ortoleva-King reaction to provide the corresponding imidazo[1,2-a]pyridines in good yields with low catalyst loading (0.8 mol%). Moreover, the heterogeneous catalyst can be successfully employed in gram-scale synthesis and reused many times without the significant loss of catalytic activity.

Copper-catalyzed c-h functionalization of pyridines and isoquinolines with vinyl azides: Synthesis of imidazo heterocycles

Copper(I) iodide-catalyzed oxidative C(sp2)-H functionalization of pyridines and isoquinolines for the synthesis of imidazo[1,2-a]pyridines and 2-phenylimidazo[2,1-a]isoquinolines with vinyl azides under mild aerobic conditions is reported. Goo

Copper(I) iodide-catalysed aerobic oxidative synthesis of imidazo [1,2-α]pyridines from 2-aminopyridines and methyl ketones

We report here an operationally simple copper-catalysed synthesis of imidazo [1,2-α]pyridines through C-H activation with oxidative linkage of two C-N bonds under very mild conditions using molecular oxygen as a sole oxidant. The process allows the quick assembly of imidazo [1,2-α]pyridines including the antiulcer drug zolimidine from inexpensive and readily available 2-aminopyridines and methyl ketones with broad range of functional group tolerance.

Regioselective synthesis of 2- and 3-substituted imidazo[1,2-a]pyridines

A range of 2- or 3-substituted imidazo[1,2-a]pyridines were prepared from 2-aminopyridine derivatives and gemdibromovinyl compounds by the tandem nucleophilic substitution (or nucleophilic addition)/cyclisation reaction.