Results 31 to 40 of about 5,601 (174)

Modular Chiral N-Heterocyclic Carbene Ligands for the Nickel-Catalyzed Enantioselective C–H Functionalization of Heterocycles

CHIMIA, 2020
N-Heterocyclic carbenes (NHCs) are the ligands of choice in a large variety of transformations entailing different transition metals. However, the number and variety of chiral NHCs suitable as stereo-controlling ligands in asymmetric catalysis remains ...
Johannes Diesel, Nicolai Cramer
doaj   +1 more source

Synthesis, properties and color assessment of some new 5-(3- and 4-substituted phenylazo)-4,6-dimethyl-3-cyano-2-pyridones [PDF]

Journal of the Serbian Chemical Society, 2006
A series of 5-(3- and 4-substituted phenylazo)-4,6-dimethyl-3-cyano-2-pyridones were synthesized, starting from acetylacetone and arenediazonium salt, followed by condensation with cyanoacetamide using a modified literature procedure.
Mijin Dušan, Ušćumlić Gordana, Perišić-Janjić Nada, Trkulja Ivan, Radetić Maja, Jovančić Petar   +5 more
doaj   +1 more source

Iridium‐Catalyzed Ionic Hydrogenation of Multi‐Aza Heterocycles

Angewandte Chemie International Edition, EarlyView.
Saturated nitrogen‐containing heterocycles are ubiquitous in bioactive molecules and are thus attractive synthetic targets. A readily accessible cyclometalated iridium(III) complex reduces 14 different aromatic aza heterocycles to (partially)saturated multi aza‐heterocycles enlarging accessible chemical space while displaying high tolerance toward ...
Arthur Despois, Nicolai Cramer
wiley   +1 more source

A study of substituent effects on the NH bond in alkyl and aryl 4,6-disubstituted-3-cyano-2-pyridones [PDF]

Journal of the Serbian Chemical Society, 2007
Substituent effects on the IR stretching frequencies and 1H-NMR chemical shifts of the pyridone NH group in 4- and 6-disubstituted alkyl and aryl 3-cyano- 2-pyridones were investigated.
Mišić-Vuković Milica, Jovanović Slobodanka, Mijin Dušan, Csanadi Janos, Đoković Dejan   +4 more
doaj   +3 more sources

Porous Carbon Materials for Carbon Dioxide Capture

Carbon Energy, EarlyView.
This work aims to address the current status and challenges associated with the regulation of pore structures, as well as the influence of pore structures on CO2 capture. Systematic quantitative analysis of structure–property relationships, combined with machine learning approaches, can effectively evaluate the contributions of structural ...
Zhifu Liu, Chuhan Fu, Tao Qi, Hui Zhou, Guangping Hao, Yalou Guo, Guoping Hu   +6 more
wiley   +1 more source

Stereoretentive Nucleophilic Aromatic Substitution Accesses Atropisomeric 4‐Amino‐N‐Arylquinolinium Salts

Chemistry – A European Journal, EarlyView.
Quinolin‐4‐ones were converted to chloroquinolinium salts, allowing formation of axially chiral aminoquinolinium salts via an enantioretentive SNAr reaction with a variety of amine nucleophiles. The salts have a high rotational barrier, with a racemization half‐life of ∼1000s of years.
Darren Holmes, Nia Foster, Saima Ansari, Paul Kavanagh, Paul Dingwall, Peter C. Knipe   +5 more
wiley   +1 more source

Metal‐Free Active Template: A Straightforward Route to 4‐Aminopyridinium‐Based Rotaxane Molecular Shuttles

Angewandte Chemie, Volume 138, Issue 29, 13 July 2026.
Leigh's metal‐free active template‐based SNAr of an amine on halogenopyridiniums, in the presence of a crown ether, successfully afforded 4‐aminopyridinium‐containing rotaxanes. Further molecular machinery was carried out by deprotonation‐then‐carbamoylation of the conjugated amino moiety.
Ivaylo Stoyanov, Arie van der Lee, Frédéric Coutrot   +2 more
wiley   +2 more sources

Interfacial Charge‐Transfer Enhancement via High‐Entropy Alloy Regulated MXene Heterostructures for Asymmetric Supercapacitor Applications

ENERGY &ENVIRONMENTAL MATERIALS, EarlyView.
A novel core‐shell HEA@MXene composite was synthesized to enhance supercapacitor electrochemistry. DFT simulations reveal the role of HEA doping in regulating the MXene interface. The HEA@MXene composite exhibits a high specific capacitance of 872 F g−1 at 1 A g−1 with remarkable stability in 1 M KOH.
Fenhong Song, Ruibo Zhang, Wanlong Chu, Zengqiang Tan, Long Ma, Jing Fan, Gang Wang, Qi Qi, Yang Cao   +8 more
wiley   +1 more source

Synthesis of New Aza-Heterocyclic Based on 2-Pyridone

Chemistry Proceedings
In this work, we present new methods of synthesis of different molecules including a 2-pyridone nucleus. First, we prepared a series of 1H-free 2-pyridones and N-alkyl 2-pyridones from ethyl cyanoacetate, aromatic aldehydes, various acetophenone ...
Ikram Baba-Ahmed, Zahira Kibou, Julio A. Seijas, Noureddine Choukchou-Braham, M. Pilar Vázquez-Tato   +4 more
doaj   +1 more source

Binuclear Copper‐Dependent Oxidative Enzymes Involved in Fungal Natural Product Modifications

Journal of the Chinese Chemical Society, EarlyView.
This article summarizes recent biochemical characterizations of a new enzyme family named by the authors as binuclear copper‐dependent oxidative enzymes (BiNCOs). Found in fungal natural product biosynthesis, BiNCOs catalyze diverse CH functionalization reactions, including C(sp3)H halogenation, C(sp3)H hydroxylation, C(sp3)O macrocyclization, and ...
Chen‐Yu Chiang, Masao Ohashi, Yi Tang
wiley   +1 more source