5352-95-4

Upstream product

• 5319-46-0 N-(4-fluoro-phenyl)-N-nitroso-glycine 
• 2521-99-5 2-(4-fluorophenylamino)acetic acid ethyl ester 
• 460-00-4 1-Bromo-4-fluorobenzene 
• 105-36-2 ethyl bromoacetate 
• 371-40-4 4-fluoroaniline 
• 351-95-1 N-(4-fluoro-phenyl)-glycine 

Downstream Products

• 68657-34-1 alpha-(2-(2,2-dicyanovinyl)-2-(4-fluorophenyl)hydrazono)malononitrile 
• 823-85-8 4-fluorophenyhydrazine hydrochloride 
• 190730-99-5 (E)-(η(5)-C5Me5)(CO)2FeP=CHN(4-FC6H4)N=C(NMe2)2 
• 1324008-92-5 3-bromo-1-(4-fluorophenyl)-5-iodo-1H-pyrazole 
• 1324008-97-0 5-(benzo[d][1,3]dioxol-5-yl)-3-bromo-1-(4-fluorophenyl)-1H-pyrazole 
• 1324008-98-1 methyl 4-[3-bromo-1-(4-fluorophenyl)-1H-pyrazol-5-yl]benzoate 
• 1324009-00-8 3-bromo-1-(4-fluorophenyl)-5-(3-trifluorophenyl)-1H-pyrazole 
• 1324009-01-9 3-bromo-1-(4-fluorophenyl)-5-(furan-3-yl)-1H-pyrazole 
• 1324008-79-8 C₈H₄FIN₂O₂ 
• 1324009-02-0 4-[3-bromo-1-(4-fluorophenyl)-1H-pyrazol-5-yl]pyridine 
• 1324009-04-2 4-[3-bromo-1-(4-fluorophenyl)-1H-pyrazol-5-yl]-2-chloropyridine 
• 1324009-05-3 3-bromo-1-(4-fluorophenyl)-5-(prop-1-en-2-yl)-1H-pyrazole 
• 1324009-06-4 3-bromo-5-cyclopropyl-1-(4-fluorophenyl)-1H-pyrazole 
• 1324009-08-6 4-[3-cyclopropyl-1-(4-fluorophenyl)-1H-pyrazol-5-yl]pyridine 

Relevant academic research and scientific papers

Water-Involved Ring-Opening of 4-Phenyl-1,2,4-triazoline-3,5-dione for “Photo-Clicked” Access to Carbamoyl Formazan Photoswitches In Situ

Cyclic azodicarbonyl derivatives, particularly 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD), commonly serve as arenophile, dienophile, enophile and electrophile. Perplexed by its instability in aqueous environment, there are few studies focused on the transient intermediate produced by hydrolysis of PTAD to achieve synthetic significance. Herein, we describe a “photo-click” method that involves nitrile imine (NI) from diarylsydnone to capture the diazenecarbonyl-phenyl-carbamic acid (DACPA) generated by water-promoted ring-opening of PTAD. DFT calculation reveal that H-bonding interactions between PTAD and water are vital to form DACPA which exhibited an umpolung effect during ligation by nature bond orbit (NBO) analysis. The ultra-fast ligation resulted in carbamoyl formazans, as a unique Z?E photo-switchable linker on target molecules, including peptide and drugs, with excellent anti-fatigue performance. This strategy is showcased to construct highly functionalized carbamoyl formazans in situ for photo-pharmacology and material studies, which also expands the chemistry of PTAD in aqueous media.

Exploiting Synergistic Catalysis for an Ambient Temperature Photocycloaddition to Pyrazoles

Sydnone-based cycloaddition reactions are a versatile platform for pyrazole synthesis, however they operate under harsh conditions (high temperature and long reaction times). Herein we report a strategy that addresses this limitation utilizing the synergistic combination of organocatalysis and visible-light photocatalysis. This new approach proceeds under ambient conditions and with excellent levels of regiocontrol. Mechanistic studies suggest that photoactivation of sydnones, rather than enamines, is key to the successful implementation of this process.

Photo-accelerated "click" reaction between diarylsydnones and ring-strained alkynes for bioorthogonal ligation

We constructed a library of diarylsydnone (DASyd) candidates in search of a photoclickable reaction toward alkynes, enabling an ultra-accelerated reactivity, while suppressing the background cycloaddition in the dark. The in vitro and in vivo protein labe

Synthesis and evaluation of photo-activatable β-diarylsydnone-L-alanines for fluorogenic photo-click cyclization of peptides

Herein, we design and synthesize a series of photoactivatable β-diarylsydnone-l-alanines (DASAs), which have excellent photo-reactivity with high fluorescence turn-on toward alkenes in a biocompatible environment. The environmental sensing properties of t

Novel sydnone derivatives carrying azidomethyl-1,2, 4-oxadiazole unit and their 1,3-dipolar cycloadditions

A series of 1,2,4-oxadiazolymethyl sydnones carrying azido group were synthesized and subjected to react with a variety of alkenic and acetylenic dipolarophilic reagents; N-phenyl maleimide, phenyl vinyl sulfone, and phenyl propiolic acid. All the new products are identified by spectral/physical data including high-resolution mass measurements and X-ray diffraction data.

Expanding available pyrazole substitution patterns by sydnone cycloaddition reactions

We report the use of alkynylsilanes for the regiocontrolled synthesis of pyrazoles from functionalised sydnones. The strategies outlined herein allow a range of pyrazoles to be accessed with substitution patterns that are otherwise not directly obtained with high selectivity by alkyne cycloadditions. Moreover, this study serendipitously highlighted a simple and convenient procedure for the synthesis of aryl monofluoromethyl ethers through the combination of TBAF and dichloromethane.

Synthesis of aminopyrazoles from sydnones and ynamides

Aminopyrazoles are prepared from readily accessible sydnones and sulfonyl ynamides using either a copper-mediated sydnone alkyne cycloaddition (CuSAC) or in situ generated strained cyclic ynamides.

Ultrafast Click Chemistry with Fluorosydnones

We report the synthesis and reactivity of 4-fluorosydnones, a unique class of mesoionic dipoles displaying exquisite reactivity towards both copper-catalyzed and strain-promoted cycloaddition reactions with alkynes. Synthetic access to these new mesoionic compounds was granted by electrophilic fluorination of σ-sydnone PdIIprecursors in the presence of Selectfluor. Their reactions with terminal and cyclic alkynes were found to proceed very rapidly and selectively, affording 5-fluoro-1,4-pyrazoles with bimolecular rate constants up to 104m?1s?1, surpassing those documented in the literature with cycloalkynes. Kinetic studies were carried out to unravel the mechanism of the reaction, and the value of 4-fluorosydnones was further highlighted by successful radiolabeling with [18F]Selectfluor.

Synthesis and evaluation of phenyl substituted sydnones as potential DPPH-radical scavengers

A series of phenyl substituted sydnones has been synthesized and their radical-scavenging activity has been studied on DPPH free radical. Out of eighteen compounds screened, nine compounds show interesting activity. A mechanism is presented whereby sydnones scavenge DPPH radical through donating H-atom at 4th-position. Its strong radical-scavenging activity mainly arises from 1, 2, 3-oxadiazolium-5-olate ring. Different substituents and their positions on the phenyl ring differently influence DPPH scavenging activity and therefore, may provide clues to design and develop better free-radical scavenging sydnones with multiple activities.

Reactions of 4-acetylsydnones with hydrazine: Formation of 2,4- dihydropyrol-3-ones

Reactions of 4-acetylsydnones with hydrazine at room temperature yielded a series of 2,4-dihydropyrazol-3-ones. The cycloaddition via sydnone rings with loss of a nitrogen oxide ion is a new type of reaction for the application of sydnone in organic synth