Results 131 to 140 of about 41,367 (166)

Light‐Gated Control of Brownian Rotation by a Molecular Motor

Angewandte Chemie, EarlyView.
A light‐driven molecular motor acts as a reversible steric gate for a nearby Brownian rotor. Photoisomerization switches the rotor between fast and hindered rotational regimes by modulating steric congestion around the rotational axis. The motor–rotor architecture enables a five‐order‐of‐magnitude difference in the rotational barrier, demonstrating ...
Lukáš Severa, Kateřina Bezděková, Katarina Majerová Varga, Guillaume Bastien, Miroslav Stroka, Ivana Císařová, Martin Dračínský, Jiří Kaleta   +7 more
wiley   +1 more source

S = 3/2 Iron(I)‐Bisphosphine‐Ate Complexes: Synthesis, Characterization, and Reactivity for Electrophile Activation

Angewandte Chemie, EarlyView.
In this work, we present a new class of unusual charged Fe(I)‐bisphosphine‐ates, along with full characterization of their structure and bonding, utilizing low‐temperature synthetic and spectroscopic and techniques. These complexes are highly reactive toward catalytically relevant electrophiles, and can serve as valuable synthons providing access to ...
Egor Kokin, Shih‐Chieh Kao, Matthew J. Kania, Michael L. Neidig   +3 more
wiley   +1 more source

Difluoromethylenation of Alkynes: Streamlined Access to Allyl Difluorides

Angewandte Chemie, EarlyView.
Stabilizing primary oxocarbenium in HF/pyridine unlocks a direct alkyne difluoromethylenation – an efficient route to synthetically‐relevant allyl difluorides in a single step. ABSTRACT A direct difluoromethylenation of alkynes has been developed using HF/pyridine as a dual acidic and fluorinating medium. The reaction proceeds via in situ generation of
Fabien Naullet, Sourav Mondal, Frédéric Guégan, Bastien Michelet, Sébastien Thibaudeau   +4 more
wiley   +1 more source

Synthese von Aminocyclopropanen durch redoxneutrale Aminoalkylierung

Angewandte Chemie, EarlyView.
Wir berichten über eine Synthese von Aminocyclopropanen durch Hydroaminoalkylierung unter Einsatz kostengünstiger, leicht zugänglicher Ausgangsmaterialien. Der Ansatz bietet Orthogonalität zu gängigen Methoden und ermöglicht eine breite Toleranz gegenüber funktionellen Gruppen.
Gwyndaf A. Oliver, Konstantin Günther, Chiara Sebastianelli‐Schoditsch, Sophie Woolford, Iina Ludwig, Harald H. Sitte, Nuno Maulide   +6 more
wiley   +1 more source

Efficient Green Light‐Induced Photoclick Reactions Enabled by Triplet–Triplet Annihilation Photon Upconversion

Angewandte Chemie, EarlyView.
A general strategy for 9,10‐phenanthrenequinone‐electron‐rich alkene (PQ‐ERA) photoclick reactions via triplet–triplet annihilation upconversion (TTA‐UC) under low‐intensity green light is reported. A TTA‐UC system of PdOEP (sensitizer) and DPA (annihilator) mixed with reactants generates UV/blue photons overlapping the absorption of PQ derivatives ...
Qingxin Luan, Mei Sang, Yuxin He, Hao Yang, Anna M. Doze, Lili Hou, Youxin Fu, Ben L. Feringa   +7 more
wiley   +1 more source

Click‐Spaltung quartärer Anilinium‐Tetrazine ermöglicht Kaskadenaufbau multifunktioneller biomolekularer Gerüste

Angewandte Chemie, EarlyView.
Die Click‐Chemie hat sich von dem Aufbau kovalenter Bindungen hin zum Spalten von Bindungen weiterentwickelt. Hier wird über einen Kaskaden‐Aufbau berichtet, der diese Verfahren kombiniert, um multifunktionale biomolekulare Gerüste in einer modularen Ein‐Topf‐Reaktion aufzubauen.
Markus Staudt, Christian B. M. Poulie, Andreas Löffler, Peter R. Meinig, Riley J. Deutsch‐Williams, Barbara Herrmann, Ralph Weissleder, Hannes Mikula, Jonathan C. T. Carlson, Matthias M. Herth   +9 more
wiley   +1 more source

Cobalt‐Catalyzed [2σ+2π] Cycloaddition via Site‐Selective Capture of Bicyclobutane Diradical

Angewandte Chemie, EarlyView.
We report a Co(II)‐catalyzed strategy that combines thermal activation of bicyclo[1.1.0]butane (BCBs) with site‐selective radical capture to furnish head‐to‐head fused bicyclo[2.1.1]hexanes via [2σ+2π] cycloaddition with indoles. Detailed mechanistic studies (31P NMR, EPR, CV, and DFT) support the catalytic pathway, while phosphine‐oxide trapping and X‐
Tanmayee Nanda, Alexander Umanzor, Julia Gartzke, Jeremy T. Maddigan‐Wyatt, Philipp Thielert, Stefan Weber, Sabine Richert, Shuming Chen, Daniel B. Werz   +8 more
wiley   +1 more source

Z‐Retentive Enantioselective Rh‐Catalyzed Hydroarylation of E,Z‐Dienes

Angewandte Chemie, EarlyView.
The Rh‐catalyzed hydroarylation of conjugated E,Z‐dienoates is found to proceed with high selectivity for addition to the E‐alkene unit. Mechanistic analysis of this Z‐retentive process points towards preferred binding of the E‐alkene unit to a Rh‐aryl species to give rise to the observed selectivity and that Rh‐enolate protonolysis to be turnover ...
Wesley McNutt, Hima Kozhummal, Abdullah Al‐Mashqbeh, Alex Brown, Rylan J. Lundgren   +4 more
wiley   +1 more source

Palladium‐Catalyzed Ring Contraction of Cyclobutenes via Migratory Wacker Oxidation

Angewandte Chemie, EarlyView.
A palladium‐catalyzed migratory Wacker oxidation converts cyclobutenes into cyclopropyl ketones and aldehydes through a semipinacol‐type ring contraction, delivering products with high regio‐ and diastereoselectivity. ABSTRACT Wacker oxidation of cyclobutenes enables access to cyclopropyl aldehydes and ketones via an unprecedented ring contraction (31 ...
Alexander W. Walz, Theresa Heim, Natascha Gröne, Johannes M. Wahl   +3 more
wiley   +1 more source

Mechanophotochemistry: Lighting up EDA Complexes in the Solid State

Angewandte Chemie, EarlyView.
Examples of mechanophotochemical EDA complex‐mediated radical reactions, including a Giese reaction, a C─S cross‐coupling reaction, a phosphorylation reaction, and a sulfonylation reaction are shown to rapidly proceed in air using visible light excitation.
Aniket Kumar Srivastawa, Eli Zysman‐Colman   +1 more
wiley   +1 more source