Results 151 to 160 of about 42,305 (289)

From [NHC─H]• to Persistent σ‐Complex Radicals: Photoinduced Radical Chemistry of Imidazolium Salts

Angewandte Chemie, EarlyView.
Visible‐light excitation of electron donor–acceptor (EDA) complexes between imidazolium salts and triarylamines enables controlled single‐electron transfer (SET) and reveals a family of carbene‐centered σ‐complex radical cations. Cryogenic electron paramagnetic resonance (EPR) captures the elusive [NHC─H]• intermediate and its thermal evolution into ...
Filipp M. Kolomeychuk, Lars J. C. van der Zee, Simon Mathew, Bas de Bruin, J. Chris Slootweg   +4 more
wiley   +2 more sources

Bent N‐Heterocyclic Allenes From a Well‐Defined Titanium Vinylidene Complex

Angewandte Chemie, EarlyView.
The syntheses and the structures of N‐heterocyclic allenes are reported. Allenes bearing fluorenylidene capping groups show markedly bent C═C═C units, a carbene‐like reactivity, and they can act as potent C‐donor ligands for metal complexes. ABSTRACT Allenes typically display a linear geometry. A notable exception occurs in allenes bearing two electron‐
Bastiaan Kooij, Damien W. Chen, Rosario Scopelliti, Farzaneh Fadaei‐Tirani, Kay Severin   +4 more
wiley   +2 more sources

Iterative Synthesis of Pentacene Derivatives with Continuous Boron–Oxygen Bonds

Angewandte Chemie, EarlyView.
An iterative synthetic strategy enables the controlled introduction of continuous multiple B–O bonds at the zigzag edge of acenes. A simple two‐step cycle—ipso iodination and Suzuki cross‐coupling/condensation—efficiently constructs BO‐acenes ranging from naphthalene to pentacene.
Seonghwa Jeong, Si‐In Kim, Jonghwan Lee, Hwon Kim, Jinuk Jang, Jiyeon Kim, Wonyoung Choe, Seung Kyu Min, Young S. Park   +8 more
wiley   +2 more sources

Porous Phenazine‐bridged Tetraoxa[8]Circulenes for Selective Gold Recovery and Heterogeneous Catalysis

Angewandte Chemie, EarlyView.
Gold recycling from electronic waste using porous materials is an emerging concept to reduce the environmental impact of gold mining. In this work, we report the synthesis of a highly porous phenazine‐derived tetraoxa[8]circulene polymer and its utilization in gold capture and heterogeneous catalysis.
Patrick W. Fritz, Eylül Attar, Timur Ashirov, Krzysztof Piech, Ali Coskun   +4 more
wiley   +2 more sources

Strategies Toward Accessing Enantioenriched (Hetero)Benzo‐Fused 5‐ and 6‐ Membered Rings via Intermolecular Carbometalation

Angewandte Chemie, EarlyView.
The use of transition‐metal catalysts and design of chiral ligands have allowed chemists to access highly functionalized benzofused 5‐ and 6‐ membered rings in high yield and enantioselectivity. A common strategy used relies on an intermolecular carbometalation across alkynes and olefins, usually followed by a subsequent intramolecular carbometalation.
Clara Jans, Armaan Grewal, Xavier Abel‐Snape, Mark Lautens   +3 more
wiley   +2 more sources

Alcohol‐Directed Carboamination of Conjugated Enynes

Angewandte Chemie, EarlyView.
The first general three‐component intermolecular Pd‐catalyzed carboamination of conjugated enynes enables the coupling of anilines and aryl triflates to produce functionalized allenic amines, utilizing a native alcohol directing group to control regioselectivity.
Helena Solé‐Àvila, Duncan K. Brownsey, Hugo Senelle, Jerome Waser   +3 more
wiley   +2 more sources

Intermolecular Electrophilic Germylation Using GeCl4 and Al2Cl6

Angewandte Chemie, EarlyView.
While electrophilic aromatic substitution is well‐established for carbon and silicon‐based electrophiles, it is extremely underdeveloped for germanium. Herein we report the first effective intermolecular Germa–Friedel–Crafts reaction. The process can be modified to enable selective synthesis of the mono‐ or the di‐aryl germane derivatives, ArGeCl3 and ...
Justyna Łosiewicz, Milan Kumar Bisai, Zachary A. Bub, Stuart A. Macgregor, Michael J. Ingleson   +4 more
wiley   +2 more sources

In‐situ‐Konstruktion von Imidazopyridinium‐Fluoreszenzlabels für Biokonjugationen

Angewandte Chemie, EarlyView.
Durch Chromophor‐Engineering von Isochinolinaldehyden entstehen TICT‐basierte fluorogene Farbstoffe für die In Situ Markierung unterschiedlicher (Bio‐)Moleküle mit großen Stokes‐Verschiebungen, die mit der Zellbildgebung kompatibel sind. ZUSAMMENFASSUNG Einfache, effiziente Transformationen fluorogenen Charakters, die unter biokompatiblen Bedingungen ...
Dongchen Du, László Albert, Milan Weitzel, Linda E. Eijsink, Elena R. Cotroneo, Dennis Marzin, Felipe Opazo, Nadja A. Simeth   +7 more
wiley   +1 more source

Homoleptic and Heteroleptic Borylones L1‐B(Ph)‐L2

Angewandte Chemie, EarlyView.
Density functional theory and CCSD(T) calculations reveal that homoleptic and heteroleptic borylones L1–B(Ph)–L2 are thermodynamically accessible. Remarkably, the homoleptic borylones B(Ph)(N2)2 and B(Ph)(SPh2)2 exhibit higher bond dissociation energies than the related carbones.
Qin Ma, Wei Li, Ya Hu, Lili Zhao, Gernot Frenking   +4 more
wiley   +2 more sources

Two‐Dimensional Polymers as Modular Metal‐Free Solid‐State Catalysts for Efficient Sono‐Piezo‐Photocatalytic Hydrogen Peroxide Production

Angewandte Chemie International Edition, EarlyView.
This study demonstrates the high piezo‐photocatalytic activity of solid molecular catalysts (SMCs) in the production of hydrogen peroxide from water and oxygen. Through the rational design of molecular motifs (diphenylpyridine or terpyridine) and backbone functionalities (methyl group, aliphatic amine antenna, or aromatic pyrrole unit), as well as ...
Sarah Brettschneider, Keanu V. A. Birkelbach, Marcus Lantzius‐Beninga, Ahmed Mourran, Gurudas Chakraborty, Peter J. C. Hausoul, Andreas Herrmann, Regina Palkovits   +7 more
wiley   +1 more source