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• 98-59-9 p-toluenesulfonyl chloride 
• 106-49-0 p-toluidine 
• 36719-51-4 3,3-diethyl-1-(4-methylphenyl)-1-triazene 
• 106-38-7 para-bromotoluene 

Relevant academic research and scientific papers

Pyrazole-3-carboxylates assisted N-heterocyclic carbene palladium complexes: synthesis, characterization, and catalytic activities towards arylation of azoles with arylsulfonyl hydrazides

Four mononuclear and dinuclear pyrazole-3-carboxylates assisted NHC–Pd complexes have been synthesized and characterized. Notably, the bridge-cleavage reactions of [Pd(μ-Cl)(Cl)(NHC)]2 with 1H-pyrazole-3-carboxylic acid afforded dinuclear complexes [(NHC)Pd(μ-1H-pyrazolato-3-carboxylate)]2, in which the 1H-pyrazolato-3-carboxylate was employed as a N^N^O dianionic chelating and bridging ligand. To further explore the structural features and catalytic properties of the complexes, 1-methyl-1H-pyrazole-3-carboxylic acid was introduced into the coordination with [Pd(μ-Cl)(Cl)(NHC)]2 and the corresponding mononuclear complexes (NHC)PdCl(1-methyl-1H-pyrazole-3-carboxylate) were obtained. The catalytic properties of the complexes in desulfitative arylation of azoles with arylsulfonyl hydrazides were initially investigated.

Palladium-catalyzed direct C2-arylation of azoles with aromatic triazenes

A highly efficient palladium-catalyzed arylation of azoles at the C2-position using 1-aryltriazenes as aryl reagents was developed. Azoles including oxazoles, thiazoles, imidazoles, 1,3,4-oxadiazoles, and oxazolines could react with 1-aryltriazenes smoothly to generate the corresponding products in good to excellent yields, and various substitution patterns were tolerated toward the reaction.

Synthesis of N-heterocyclic carbene-PdCl-[(2-Pyridyl)alkyl carboxylate] complexes and their catalytic activities towards arylation of (benzo)oxazoles with aryl bromides

Four well-defined N-heterocyclic carbene-PdCl-[(2-Pyridyl)alkyl carboxylate] complexes have been conveniently synthesized through bridge-cleavage reactions of [Pd(μ-Cl)(Cl)(NHC)]2 with (2-pyridyl)alkyl carboxylic acids [2-(pyridin-2-yl)acetic acid and 3-(pyridin-2-yl)propanoic acid]. The new complexes have been fully characterized by NMR, elemental analysis, HR-MS and X-ray single-crystal diffraction. The catalytic performance of the complexes was screened and the obtained palladium (II) complexes shown effective catalytic activities for direct arylation of (benzo)oxazoles with aryl bromides. Moreover, the 2-(pyridin-2-yl)acetate stabilized NHC–Pd complexes were more efficient than the 3-(pyridin-2-yl)propanoate stabilized NHC–Pd analogues. Further studies exhibited that 2-(pyridin-2-yl)acetate, as ancillary ligand, could easily decarboxylate and transform into 2-methylpyridine in the reaction condition.

Palladium-catalyzed desulfitative arylation of azoles with arylsulfonyl hydrazides

Palladium-catalyzed desulfitative and denitrogenative arylation of azoles with arylsulfonyl hydrazides has been achieved. A broad scope of azoles and arylsulfonyl hydrazides has been used to produce arylated azoles in high yields.