Results 131 to 140 of about 166,984 (347)

Catalytic Functionalization of Unactivated π‐Bonds Enabled by Bidentate Directing Auxiliaries

Angewandte Chemie, EarlyView.
This review explores how bidentate directing auxiliaries have advanced transition‐metal catalysis for unactivated alkene/alkyne functionalization. By leveraging chelated intermediates, bidentate directing auxiliaries enable precise hydrofunctionalization, difunctionalization, and C─H activation of π‐bonds with unique selectivity and reactivity.
Seunghyeon Cho, Al Vicente Riano D. Lisboa, Juntao Sun, Taeho Kang, Keary M. Engle   +4 more
wiley   +2 more sources

Catalytic Friedel–Crafts Reactions of Unactivated Secondary Alcohols: Site-Selective ortho-Alkylation of Phenols

, 2023
A combination of catalytic ZnCl2 and catalytic CSA enables the first site-selective Friedel–Crafts alkylation of phenolic derivatives with unactivated secondary alcohols.
Kevin, Kou, Charlene, Fan, Aaron, Pan, Lorraine, Rangel, Viviene, Nguyen   +4 more
core   +1 more source

Identification and validation of fecal complement component 3 and fibronectin as potential biomarkers for monitoring disease activity in ulcerative colitis based on a mouse model

Animal Models and Experimental Medicine, EarlyView.
This study demonstrated elevated levels of fecal component 3 (C3) and fibronectin (FN) in an ulcerative colitis (UC) mouse model. Importantly, fecal C3 exhibited a stronger correlation with disease activity than the clinically used fecal calprotectin (FC).
Yangyun Guo, Ziheng Yan, Jingyu Ye, Ruifu Yang, Yajun Song, Hui Yue, Yong Zhao   +6 more
wiley   +1 more source

Spatial Orientation‐Dependent Double Hydrogen Bond/Photoredox Cooperative Catalysis in Metal–Organic Frameworks

Angewandte Chemie, EarlyView.
We report a heterogeneous double hydrogen bond/photoredox synergistic catalysis, wherein the flexibility and spatial orientation of catalytic centers, rather than catalyst activity, play a dominant role in catalytic performance. ABSTRACT Catalyst activity is typically the primary priority in designing a catalytic system. The higher catalyst activity is
Jing Ouyang, Sze Lam Lam, Chao Li, Peiqi Zhang, Le Yang, Zhiyi Yang, Teng‐Teng Chen, Xueliang Xiao, Yangjian Quan   +8 more
wiley   +2 more sources

Pyridine C─N Transposition via Cycloaddition–Cycloreversion

Angewandte Chemie, EarlyView.
Transposition of pyridine nitrogen from the 4‐ to the 3‐position is described using two open and shut sequences: a nucleophile addition ring‐open ring‐closure, followed by a nitrile Diels–Alder cycloaddition cycloreversion. The nitrogen swap is particularly effective for tertiary alkyl substituents, transforming easily accessible para‐alkylated ...
Aífe Conboy, Michael F. Greaney
wiley   +2 more sources

A Crystalline and Thermally Stable Selenocysteine Selenenic Acid

Angewandte Chemie, EarlyView.
The long‐sought catalytic intermediate of selenoproteins, selenocysteine selenenic acid (Sec–SeOH), is isolated for the first time at ambient temperature. A bioinspired selenopeptide sequence encapsulated within a protective molecular cradle and an oxidant‐free route from selenenyl iodide (Sec–SeI) enable the isolation of Sec–SeOH. Contrary to the long‐
Ryosuke Masuda, Satoru Kuwano, Kei Goto
wiley   +2 more sources

Copper-catalyzed arylation of alkyl halides with arylaluminum reagents

Beilstein Journal of Organic Chemistry, 2015
We report a Cu-catalyzed coupling between triarylaluminum reagents and alkyl halides to form arylalkanes. The reaction proceeds in the presence of N,N,N’,N’-tetramethyl-o-phenylenediamine (NN-1) as a ligand in combination with CuI as a catalyst.
Bijay Shrestha, Ramesh Giri
doaj   +1 more source

Mitochondria‐Targeting Moieties Based on N‐Tethered Pyridinium Cations

Angewandte Chemie, EarlyView.
Pyridinium cations were benchmarked as mitochondria‐targeting moieties in a panel of N‐tethered fluorescent‐, bioactive‐, and inert‐cargo conjugates. 3,5‐Diphenylpyridinium (DPPy+) is a competent triphenylphosphonium (TPP+) surrogate, combining high mitochondria‐targeting efficiency with lower intrinsic effects on mitochondrial function.
Ivan Džajić, Natalija Trunkelj, Jernej Repas, Maša Kandušer, Lara Smrdel, Stane Pajk, Lovro Žiberna, Irena Mlinarič‐Raščan, Bostjan Markelc, Tim Bozic, Masa Omerzel, Tanja Jesenko, Maja Cemazar, Katja Kološa, Bojana Žegura, Miha Virant, Matic Lozinšek, Hai M. Nguyen, Joshua A. Nasburg, Heike Wulff, Maxime Gueguinou, Valerije Vrček, Veronica Carpanese, Ildiko Szabo, Luis A. Pardo, Tihomir Tomašič, Lucija Peterlin Mašič, Andrej Emanuel Cotman   +27 more
wiley   +2 more sources

Cymenes. 1. Modern state of processes for producing cymenes

Тонкие химические технологии, 2012
The article analyzes methods for the preparation of cymenes based on using petrochemical raw materials: toluene and propylene/isopropanol. It is concluded that at present advanced technologies for the production of individual cymenes are absent, and the ...
T. N. Nesterova, G. N. Koshel, Yu. B. Rumyantseva, E. A. Kurganova, S. V. Vostrikov, V. A. Shakun   +5 more
doaj  

1,4-Dibenzyl-6-chloroquinoxaline-2,3(1H,4H)-dione

IUCrData, 2017
The title compound, C22H17ClN2O2, crystallizes with two independent molecules (A and B) in the asymmetric unit. The 6-chloroquinoxaline-2,3(1H,4H)-dione ring system is essentially planar.
Ali El Janati, Youssef Kandri Rodi, Jerry P. Jasinski, Manpreet Kaur, Younes Ouzidan, El Mokhtar Essassi   +5 more
doaj   +1 more source