Results 91 to 100 of about 3,124,995 (289)

Selective detection of fluoride based on a pyridinium n-phenolate-calix[4]pyrrole displacement assay: an undergraduate laboratory experiment

Química Nova, 2014
A two-step experiment is proposed for a third year class in experimental organic chemistry. Over a period of five weeks, the students synthesized calix[4]pyrrole, a receptor that is highly selective for fluoride, and a pyridinium N-phenolate dye ...
Karina Mannrich, Marcelo Silva, Leandro G. Nandi, Celso R. Nicoleti, Vanderlei G. Machado   +4 more
doaj   +1 more source

Synthesis of chiral 2-methyl-5,6,7,8-tetrahydroquinolines from naturally occurring monoterpenes [PDF]

, 2004
The synthesis is reported of chiral substituted 2-methylpyridines, in which the pyridine rings are annulated at the 5,6-positions to the chiral frameworks originating from (-)-β-pinene, (-)-isopinocampheol and (+)-camphor.
Chelucci, Giorgio Adolfo, Orrù, Gianmauro, Soccolini, Francesco   +2 more
core  

Organophotoredox/Cobalt‐Catalyzed Retro‐Hydroformylation of Aldehydes

ChemistryEurope, EarlyView.
A new photoredox/cobalt retro‐hydroformylation is developed. This one‐pot two‐step process involves the in situ formation of the corresponding 1,4‐dihydropyridine as key intermediate. Under mild reaction conditions, alkenes are efficiently produced from a wide range of aliphatic α‐monosubstituted aldehydes, with high functional‐group tolerance.
Augustin Nouaille, Emmanuel Magnier, Corinne Gosmini, Guillaume Dagousset   +3 more
wiley   +1 more source

Suzuki reaction on pyridinium N-haloheteroarylaminides: regioselective synthesis of 3,5-disubstituted 2-aminopyrazines [PDF]

, 2008
An extensive study of Suzuki–Miyaura cross-coupling processes on N-pyridinium bromoazinyl aminides has been performed. Mono- and disubstitution on 5- and 3,5-bromo derivatives produced the corresponding aryl derivatives.
Castillo Romero, Rafael, Izquierdo Ceinos, Ma Luisa, Reyes Prados, María Jose, Álvarez-Builla Gómez, Julio   +3 more
core   +2 more sources

Skeletal Editing from Pyridine to Aniline via C‐Insertion and N‐Isomerization

ChemistryEurope, EarlyView.
A concise protocol is presented that converts pyridines into anilines by externalizing the original pyridine nitrogen at either the "ipso" or "ortho" position, which results in para or meta‐primary aniline products. A key carbene‐insertion step precedes nitrogen migration, preserving both ring size and overall structure.
Yun Luo, Jing Dai, Yongchang Wei, Chang Min   +3 more
wiley   +1 more source

4,4′-(Anthracene-9,10-diylbis(ethyne-2,1-diyl))bis(1-benzyl-1-pyridinium) Bromide

Molbank
Viologens, i.e., quaternary 4,4′-bipyridinum salts, are a well-known class of functional organic compounds that have attracted in the past few decades a great deal of attention for their peculiar chemical and electrochemical properties and have therefore
Valentina Novelli, Andrea D’Annibale, Fabrizio Casano, Alessandro Latini, Lorenza Romagnoli   +4 more
doaj   +1 more source

Pyridinium N-(2'-azinyl)aminides: Regioselective synthesis of 2-alkylaminoazines [PDF]

, 2000
The regioselective alkylation of pyridinium-N-(2'-azinil)aminides with alkyl halides under mild conditions is described. The alkylation, combined with a reduction of the N-N bond, allows an easy preparation of 2-alkylaminoazines.The authors wish to thank
Burgos Gómez, Carolina, Delgado Jiménez, Francisca, García Navío, José Luis, Izquierdo Ceinos, Ma Luisa, MartÍnez Barrasa, Valentín, Álvarez-Builla Gómez, Julio   +5 more
core   +3 more sources

Shedding Light on Synthetic Autocatalysis: From Conventional Closed‐Shell Chemistries to Overlooked Open‐Shell Occurrences

Chemistry – A European Journal, EarlyView.
Why add another catalyst when the product itself holds the power to catalyze its own formation? Autocatalysis in synthetic chemistry enhances reaction efficiency and uncovers novel catalytic behavior across both closed‐shell and open‐shell systems, expanding reactivity and enabling innovative design strategies.
Jaspreet Kaur, Joshua P. Barham
wiley   +1 more source

Synthesis and disinfection effect of the pyridine-4-aldoxime based salts [PDF]

, 2015
PubMed ID: 25719739A set of new quaternary ammonium compounds based on pyridine-4-aldoxime was synthesized, characterized with analytical data (NMR, EA, HPLC, MS) and tested for in vitro antimicrobial activity (antibacterial, antifungal) and cytotoxicity.
Doležal, Martin, Doležal, Rafael, Kuča, Kamil, Maliňák, David, Marek, Jan, Pasdiorová, Markéta, Soukup, Ondřej   +6 more
core   +3 more sources

Membrane Engineering for Battery Systems: Bridging Design Principles and Frontier Applications

ENERGY &ENVIRONMENTAL MATERIALS, EarlyView.
The review emphasizes membrane separators' role in battery performance and safety, covering redox flow, lithium‐ion, and solid‐state batteries. It reviews advances in membrane materials (e.g., polymer electrolytes, hybrid composites) and ion transport mechanisms, while addressing challenges like dendrite growth and crossover losses.
Xiaoqun Zhou, Justice Delali Akoto, Rui Tan, Jun Ma   +3 more
wiley   +1 more source