Results 31 to 40 of about 5,533 (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

Late‐Stage Functionalization of Peptides on the Solid Phase

Angewandte Chemie International Edition, EarlyView.
Peptide modifications are essential to control pharmacodynamic and pharmacokinetic properties of peptide drugs. Consequently, strategies that allow for efficient and rapid incorporation of non‐canonical modifications into peptides in parallel formats are highly sought after.
Marius Werner, Truc Lam Pham, Franziska Thomas   +2 more
wiley   +1 more source

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

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

Pd(II)‐Catalyzed Strategies for the β‐Arylation of α‐Amino Acids: An Overview

Chemistry – A European Journal, EarlyView.
The graphical abstract summarizes the review “Pd(II)‐Catalyzed Strategies for the β‐Arylation of α‐Amino Acids: An Overview”, highlighting representative Pd(II)‐catalyzed methods for the β‐arylation of α‐amino acids. Key mechanistic features, substrate diversity, and synthetic relevance of these transformations are showcased. Abstract Metal‐catalyzed C─
Davide Illuminati, Claudio Trapella, Vinicio Zanirato, Virginia Cristofori, Anna Fantinati   +4 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

Photochemistry of Aromatic N‐Oxides in Water Probed by Time‐Resolved X‐ray Absorption Spectroscopy

Chemistry – A European Journal, EarlyView.
Time‐resolved XAS at the nitrogen and oxygen K‐edges is applied to the photorearrangement of two N‐oxides in water. Pyridine N‐oxide rapidly forms the oxaziridine isomer. Pyridazine N‐oxide undergoes ring opening to the diazo compound, without any evidence of intermediates.
Maximilian Paradiz Domínguez, Robby Büchner, Mattis Fondell, Albert M. Brouwer   +3 more
wiley   +1 more source

Conversion Between 2‐ and 3‐Dimensional Halogen‐Bonded Networks Formed From a Single N‐Oxide/Iodoalkyne Building Block

Chemistry – A European Journal, EarlyView.
Open halogen‐bonded networks have been prepared from building blocks that incorporate both iodoalkyne halogen bond donors and a pyridine‐N‐oxide halogen bond acceptor. An initially‐formed 3D network containing dioxane in its channels undergoes an unprecedented transition to a 2D material when crystals are exposed to diethyl ether.
Jordan N. Smith, Courtney Ennis, Huan V. Doan, Valeska P. Ting, Nicholas G. White   +4 more
wiley   +1 more source

O- and N-Difluoromethylation of 2-Pyridones with Chlorodifluoromethane

Журнал органічної та фармацевтичної хімії
Difluoromethylation of various 2-pyridones with the available industrial reagent chlorodifluoromethane (Freon-22) has been studied. Some relationships between the ratio of difluoromethylation products and the reaction conditions, as well as the presence ...
Kirill I. Petko, Andrey A. Filatov
doaj   +1 more source