1173294-85-3

Upstream product

• 4783-68-0 2-phenoxypyridine 
• 108-88-3 toluene 
• 98-88-4 benzoyl chloride 
• 109-04-6 2-bromo-pyridine 
• 108-95-2 phenol 
• 100-52-7 benzaldehyde 
• 100-42-5 styrene 
• 536-74-3 phenylacetylene 
• 100-51-6 benzyl alcohol 
• 109-09-1 2-chloropyridine 
• 1246301-62-1 C₂₆H₂₃N₂O₆Pd₂ 
• 95-56-7 2-hydroxybromobenzene 
• 23951-01-1 <2-D>-phenol 
• 98-86-2 acetophenone 

Downstream Products

• 117-99-7 2-Hydroxybenzophenone 
• 6344-60-1 1-hydroxy-9H-fluoren-9-one 
• 1446517-45-8 (2-(pyridin-2-yloxy)-1,3-phenylene)bis(phenylmethanone) 
• 875257-33-3 (2-hydroxy-1,3-phenylene)bis(phenylmethanone) 

Relevant academic research and scientific papers

Palladium-catalyzed decarboxylative, decarbonylative and dehydrogenative C(sp2)-H acylation at room temperature

Over the past few decades, an impressive array of C-H activation methodology has been developed for organic synthesis. However, due to the inherent inertness of the C-H bonds (e.g. ～110 kcal mol-1 for the cleavage of C(aryl)-H bonds) harsh reaction conditions have been realized to overcome high energetic transition states resulting in a limited substrate scope and functional group tolerance. Therefore, the development of mild C-H functionalization protocols is in high demand to exploit the full potential of the C-H activation strategy in the synthesis of a complex molecular framework. Although, electron-rich substrates undergo electrophilic metalation under relatively mild conditions, electron-deficient substrates proceed through a rate-limiting C-H insertion under forcing conditions at high temperature. In addition, a stoichiometric amount of toxic silver salt is frequently used in palladium catalysis to facilitate the C-H activation process which is not acceptable from the environmental and industrial standpoint. We report herein, a Pd(ii)-catalyzed decarboxylative C-H acylation of 2-arylpyridines with α-ketocarboxylic acids under mild conditions. The present protocol does not require stoichiometric silver(i) salts as additives and proceeds smoothly at ambient temperature. A novel decarbonylative C-H acylation reaction has also been accomplished using aryl glyoxals as acyl surrogates. Finally, a practical C-H acylation via a dehydrogenative pathway has been demonstrated using commercially available benzaldehydes and aqueous hydroperoxides. We also disclose that acetonitrile solvent is optimal for the acylation reaction at room temperature and has a prominent role in the reaction outcome. Control experiments suggest that the acylation reaction via decarboxylative, decarbonylative and dehydrogenative proceeds through a radical pathway. Thus we disclose a practical protocol for the sp2 C-H acylation reaction.

Platinum-Catalyzed Double Acylation of 2-(Aryloxy)pyridines via Direct C-H Activation

A unique, platinum-catalyzed, direct C-H acylation of 2-(aryloxy)pyridines with acyl chlorides is discovered. The reaction requires neither an oxidant nor other additives. When both ortho positions of the aryl group are accessible, the double acylation oc

NHPI and palladium cocatalyzed aerobic oxidative acylation of arenes through a radical process

The NHPI and palladium cocatalyzed radical oxidative acylation of arenes with aldehydes and alcohols as acyl equivalents via selective C-H functionalization has been described. Molecular oxygen, the most environmentally friendly oxidant, was used as the terminal oxidant in this catalytic cycle.

Aerobic oxidation of PdII to PdIV by active radical reactants: Direct C-H nitration and acylation of arenes via oxygenation process with molecular oxygen

A Pd-catalyzed aerobic oxidative C-H nitration and acylation of arenes with simple and readily available tert-butyl nitrite (TBN) and toluene as the radical precursors has been developed. Molecular oxygen is employed as the terminal oxidant and oxygen source to initiate the active radical reactants. Many different directing groups such as pyridine, pyrimidine, pyrazole, pyridol, pyridylketone, oxime, and azo groups can be employed in these novel transformations. The PdII/PdIV catalytic cycle through a radical process is the most likely pathway for these oxidative C-H nitration and acylation reactions.

Palladium-catalyzed direct ortho aroylation of 2-phenoxypyridines with aldehydes and catalytic mechanism investigation

A direct ortho aroylation of 2-phenoxypyridines with aldehydes leading to aryl ketones by the use of palladium(II) acetate, tert-butyl hydroperoxide, and chlorobenzene as the catalyst, oxidant, and solvent, respectively, is presented. Intra- and intermolecular kinetic isotope effects, radical trapping, and controlled experiments were carried out to support the proposed catalytic mechanism for the reaction. Syntheses of (2-hydroxyphenyl)(phenyl)methanones and 1-hydroxy-9H-fluoren-9-ones directed from ortho-aroylated 2-phenoxypyridines were demonstrated.

Pd(ii)-catalysed o-aroylation of directing arenes using terminal aryl alkenes and alkynes

A substrate-directed Pd-catalysed o-aroylation strategy has been demonstrated using new aroyl surrogates viz. terminal aryl alkenes and alkynes in the presence of TBHP. By a subtle change in catalyst from Cu to Pd, a differential selectivity is observed.

Pd-catalyzed oxidative acylation of 2-phenoxypyridines with alcohols via C-H bond activation

A palladium-catalyzed oxidative acylation of 2-phenoxypyridines with benzylic and aliphatic alcohols via C-H bond activation is described. This protocol represents direct access to biologically active ortho-acylphenol derivatives, and provides new opportunities to use readily available alcohols as starting materials for catalytic acylation reactions.

Palladium-catalyzed decarboxylative coupling of α-oxocarboxylic acids with C(sp2)-H of 2-aryloxypyridines

An efficient palladium-catalyzed decarboxylative ortho-acylation of 2-aryloxypyridines with α-oxocarboxylic acids is described. In this new transformation, the aromatic C(sp2)-H bond was successfully acylated to give diverse aromatic ketones regioselectively in moderate to good yields. The pyridine group can be removed easily after the acylation to give the corresponding 2-hydroxy aromatic ketones. Copyright

Palladium-catalyzed acylation of sp2 C-H bond: Direct access to ketones from aldehydes

A palladium-catalyzed direct access to ketones from aldehydes via C-H cleavage of arenes is described. The procedure utilizes air as a clean and free terminal oxidant.