7539-22-2

Upstream product

• 1128-54-7 3-methyl-1-phenyl-1H-pyrazole 
• 5436-21-5 acetylacetaldehyde dimethyl acetal 
• 100-16-3 4-nitrophenylhydrazone 
• 14042-04-7 acetoacetaldehyde bis-(4-nitro-phenylhydrazone) 
• 7119-27-9 4-chloro-3-buten-2-one 
• 100-25-4 para-dinitrobenzene 
• 1453-58-3 3-Methylpyrazole 
• 100-39-0 benzyl bromide 
• 586-78-7 para-nitrophenyl bromide 
• 636-98-6 p-nitrobenzene iodide 
• 7697-37-2 nitric acid 

Downstream Products

• 53006-55-6 4-(3-methyl-1H-pyrazol-1-yl)aniline 
• 73225-13-5 3-methyl-4-nitro-1-p-nitrophenylpyrazole 
• 90916-84-0 4-(3-methyl-4-nitro-pyrazol-1-yl)-aniline 

Relevant academic research and scientific papers

A post-synthetically modified metal-organic framework for copper catalyzed denitrative C-N coupling of nitroarenes under heterogeneous conditions

Here we report, for the first time, the Ullmann C-N coupling reaction of nitroarenes which is achieved by using a copper containing metal-organic framework (MOF) catalyst under heterogenous conditions. The ready availability of nitroarenes and their low cost have made them ideal replacements for haloarenes as electrophilic coupling partners. Notably, the reaction protocol suppresses the by-product formation in the catalytic reaction. The catalyst has been designed and synthesized by two step post-synthesis functionalization of a MOF,viz.dabco MOF-1 with a -NH2functional group (DMOF-NH2). In the post-synthetic treatment, salicylaldehyde has been used for organic modification first and then copper(ii) was successfully incorporated onto the inner surface of the porous material. The hybrid porous solid thus obtained has been employed in the catalytic C-N coupling reaction of nitroarenes with a wide variety of amines under heterogeneous conditions, which displayed very high turnover frequencies (TOF) in catalytic reactions attesting its efficacy towards theN-arylation reaction.

Regioselective Synthesis, NMR, and Crystallographic Analysis of N1-Substituted Pyrazoles

A systematic study of the N-substitution reactions of 3-substituted pyrazoles under basic conditions has been undertaken. Regioselective N1-alkylation, -arylation, and -heteroarylation of 3-substituted pyrazoles have been achieved using K2CO3-DMSO. The regioselectivity is justified by the DFT calculations at the B3LYP/6-31G??(d) level. A consistent steric effect on chemical shift has been observed for N-alkyl pyrazole analogues. Twenty-five X-ray crystallographic structures have been obtained to confirm the regiochemistry of the major products.

Base-mediated N- And O-arylations of NH-containing heterocycles, heterocyclic amines and phenols

Nucleophilic substitution reactions of N-heterocycles such as imidazole, benzimidazole, indole and pyrazole as well as NH2 or OH containing heterocycles, with electron-deficient aryl halides in the presence of t-BuOK or K2CO3as base and DMSO as solvent are reported. A series of N-aryl azoles, unsymmetric diaryl ethers and diaryl amines were obtained in good yields.

Aromatic N-arylations catalyzed by copper-anchored porous zinc-based metal-organic framework under heterogeneous conditions

A highly porous Zn-based metal-organic framework (MOF) IRMOF-3 was covalently decorated with pyridine-2-aldehyde. The free amine group of IRMOF-3 upon condensation with pyridine-2-aldehyde affords a bidentate Schiff-base moiety in the porous matrix. The Schiff base moieties are availed to anchor copper(II) ions to display the catalyst's utility towards catalytic reactions. The catalyst was characterized by UV/Vis and IR spectroscopy, powder XRD spectrometry, SEM energy-dispersive X-ray spectrometry, and nitrogen sorption measurements. The catalyst exhibits excellent activity in catalyzing the N-arylation reaction of nitrogen-containing heterocycles with aryl bromides in DMSO medium, under mild condition (90°C) in the presence of Cs 2CO3. The porous catalyst demonstrates size selectivity towards substrate as a result of the presence of active sites inside the pores of the MOF. The anchored complex seems to be not leached or decomposed during the catalytic reactions up to five successive catalytic cycles, demonstrating practical advantages over homogeneous catalysis.

Dimethyl sulfoxide/potassium hydroxide: A superbase for the transition metal-free preparation of cross-coupling products

Potassium hydroxide (KOH) in dimethyl sulfoxide (DMSO) forms a superbasic medium that allows one to access cross-coupling products from reactions between aryl halides with various sulfur-, oxygen- and nitrogen-based nucleophiles under transition metal-free conditions. Copyright

Distinguishing features of reactions of 2-chloro- and 2,2-dichloro(bromo) vinyl ketones with alkyl- and arylhydrazines

2-Chlorovinyl alkyl ketones react with alkylhydrazines to give mixtures of 1-R-3-R′- and 1-R-5-R′-pyrazoles: The 1-R-3-R′-pyrazoles form through the heterocyclization of 2-chlorovinyl ketone alkylhydrazones whereas in the heterocyclization into 1-R-5-R′-pyrazoles N1-alkyl-N 2-(2-acylvinyl)hydrazines are involved. The regiospecific heterocyclization of 2-chloro-and 2,2-dichlorovinyl ketones with arylhydrazines and also of 2,2-dichloro(bromo)vinyl trifluoromethyl ketones with C alkylhydrazines into pyrazoles and 5-chloro(bromo)-pyrazoles proceeds through a stage of haloenones hydrazones formation. The study of the structure of the obtained 1-alkyl-3(5)-alkylpyrazoles by means of two-dimenaional 1H and 13C NMR spectroscopy and GC-MS method made it possible to assign the proton and carbon signals of isomeric pyrazoles and to establish the diagnostic ions for the pair of 1,3-and 1,5-isomers.

THE NITRATION OF SOME PHENYL-SUBSTITUTED N-HETEROCYCLES

The nitration of 3-methyl-1-phenylpyrazole using nitric acid and sulfuric acid at 0 deg C gives the p-nitrophenyl isomer as the only isolated mono nitro-product and 3-methyl-4-nitro-1-p-nitrophenylpyrazole as the dinitro-product. 3-Methyl-4-phenylpyrazole gives 3-methyl-4-p-nitrophenylpyrazole with the second nitration also occurring in the phenyl ring to give 3-methyl-4-(2',4'-dinitrophenyl)pyrazole. 2-Phenylimidazole nitrates under these conditions to give first 2-p-nitrophenylimidazole and then 4-nitro-2-p-nitrophenylimidazole whilst 4-phenylimidazole gives 4-nitro-5-p-nitrophenylimidazole readily even when the amount of nitric acid is limited to one equivalent and only traces of a mono nitro-product are found. 2-Phenylimidazoline gives solely the m-nitrophenyl isomer under the same conditions.The mixed acid nitration at 0 deg C of 4-phenylmorpholine gives 4-m-nitrophenyl- and 4-p-nitrophenylmorpholine in the ratio of about 5:1.