28710-59-0

Upstream product

• 15115-37-4 5-(4-nitro-phenyl)-1,3-diphenyl-4,5-dihydro-1H-pyrazole 
• 39833-49-3 1-phenyl-3-(4-nitrophenyl)-2-propyn-1-one 
• 100-63-0 phenylhydrazine 
• 3672-66-0 1-(4-nitrophenyl)-3-phenylprop-2-yn-1-one 
• 59-88-1 phenylhydrazine hydrochloride 
• 1222-98-6 4-nitrochalcone 
• 99-81-0 4-Nitrophenacyl bromide 
• 588-64-7 (E)-1-benzylidene-2-phenylhydrazine 
• 100-52-7 benzaldehyde 
• 937-31-5 (4-Nitrophenyl)acetylene 
• 98-88-4 benzoyl chloride 
• 62-53-3 aniline 
• 51608-60-7 N-(benzylidene)-p-methylbenzenesulfonamide 
• 5633-36-3 [3-(4-nitro-phenyl)-oxiranyl]-phenyl-methanone 

Relevant academic research and scientific papers

Photooxidation of 3,5-diaryl-1-phenyl-2-pyrazolines: Experimental and computational studies

Photooxidation of various 2-pyrazolines is studied experimentally and computationally. Experimental results show that the electron-donating/withdrawing substituents increases/decreases the rate of this photoreaction. The proposed light-induced electron-tr

One-pot regioselective synthesis of substituted pyrazoles and isoxazoles in PEG-400/water medium by Cu-free nano-Pd catalyzed sequential acyl Sonogashira coupling-intramolecular cyclization

Catalyst efficacy of in situ generated Pd-nanoparticles (PdNPs) in the regioselective one-pot synthesis of 3,5-di & 3,4,5-trisubstituted pyrazoles and 3,5-disubstituted isoxazoles in environmentally benign PEG-400/H2O medium, which involves the sequential (i) Cu-free acyl-Sonogashira coupling (ASC) and (ii) intramolecular ynone-amine cyclization under PTC conditions was described. The results of controlled experiments support the operation of two sequential catalytic cycles (ASC/cyclization) and achievement of complementary/opposite regioselectivity via ynone-bound palladium in a one-pot approach. Moreover, the in situ PdNPs recovered after the first catalytic cycle of the one-pot reaction sequence have been reused again five times successively. Besides, prior to the above studies, the efficacy of some common Pd-N-heterocyclic carbene (Pd-NHC) complexes in catalyzing the same one-pot two-step reaction sequence (Cu-free ASC/cyclization) both in water and organic solvents was also optimized. In situ generation of PdNPs from above Pd-NHCs in water was also identified, but they are not reusable due to their large size distribution.

Application of Photoclick Chemistry for the Synthesis of Pyrazoles via 1,3-Dipolar Cycloaddition between Alkynes and Nitrilimines Generated In Situ

The photochemical extrusion of gaseous nitrogen from 2,5-disubstituted tetrazoles to generate reactive nitrilimines in situ represents an efficient and attractive way to form dipoles that can be used to provide useful chemicals via 1,3-dipolar cycloadditions. The concept of “photoclick chemistry” already inspired numerous researchers, who exploited photochemical processes involving alkenes for the synthesis of adducts or the functionalization of biocompatible materials. The approach requires bioorthogonality, ease of access to the starting materials and operational simplicity. We report herein our investigations toward a photoclick reaction involving 2,5-disubstituted tetrazoles and alkynes as the dipolarophile for the synthesis of pyrazole derivatives. In addition to the numerous reports recently published on the synthesis of pyrazoles, we wish to add to the list a photochemical procedure that represents a mild and atom-economical alternative. Moreover, considering that such nitrilimines precursors can be accessed in one step from inexpensive and abundant starting materials and given the commercial availability of a broad spectrum of alkynes, we examined the scope of the photoclick reaction with respect to reactive partners, enabling the synthesis of a library of useful heteroaromatics.

Radical Addition of Hydrazones by α-Bromo Ketones to Prepare 1,3,5-Trisubstituted Pyrazoles via Visible Light Catalysis

A novel efficient tandem reaction of hydrazones and α-bromo ketones is reported for the preparation of 1,3,5-trisubstituted pyrazoles by visible light catalysis. In this system, the monosubstituted hydrazones show wonderful reaction activity with alkyl radicals, generated from α-bromo ketones. A radical addition followed by intramolecular cyclization affords the important pyrazole skeleton in good to excellent yields. This efficient strategy under mild conditions with wide group tolerance provides a potential approach to the 1,3,5-trisubstituted pyrazoles.

Facile one-pot synthesis of 1,3,5-trisubstituted pyrazoles from α,β-enones

A practical and efficient one-pot synthesis of 1,3,5-trisubstituted pyrazoles from α,β-enones and arylhydrazine hydrochlorides has been developed. The pyrazoles were formed via a tandem formation of the corresponding pyrazolines and an acid-catalyzed aerobic oxidation process.

SAR studies of differently functionalized chalcones based hydrazones and their cyclized derivatives as inhibitors of mammalian cathepsin B and cathepsin H

Cathepsins have emerged as potential drug targets for melanoma therapy and engrossed attention of researchers for development and evaluation of cysteine cathepsin inhibitors as cancer therapeutics. In this direction, we have designed, synthesized, and ass

Dess-Martin periodinane-mediated oxidative aromatization of 1,3,5-trisubstituted pyrazolines

(Chemical Equation Presented) A general method for the oxidative aromatization of 1,3,5-trisubstituted pyrazolines under mild conditions has been developed using Dess-Martin periodinane as oxidant. Copyright Taylor & Francis Group, LLC.

Silica-supported 1,3-dichloro-5,5-dimethylhydantoin (DCH) as a useful reagent for microwave-assisted aromatization of 1,3,5-trisubstituted pyrazolines under solvent-free conditions

1,3,5-Trisubstituted pyrazolines are rapidly and conveniently oxidized to their corresponding pyrazoles by 1,3-dichloro-5,5-dimethylhydantoin (DCH) in solution and solvent-free conditions under microwave irradiation. The presence of silica gel as a suppor

A convenient and efficient protocol for the synthesis of 5-aryl-1,3-diphenylpyrazole catalyzed by hydrochloric acid under ultrasound irradiation

The synthesis of 5-aryl-1,3-diphenylpyrazole via the reactions of 3-aryl-2,3-epoxy-1-phenyl-1-propanone with phenylhydrazine was carried out in 69-99% yields at room temperature under ultrasound irradiation. This method provides several advantages such as

Solvent-free synthesis of 1, 3-diphenyl-5-arylpyrazole derivatives

The synthesis of 1, 3-diphenyl-5-arylpyrazoles via the reactions of 2, 3-epoxy-1-phenyl-3-aryl-1-propanones with phenylhydrazine was carried out in 48-84% yields at 230 °C under solvent-free condition within 1.5 h. This method provides several advantages