Results 121 to 130 of about 96,389 (286)

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

Katalysatoraktivierung als Schlüsselfaktor in Kreuzkupplungen: Raumtemperatur‐Kupplungen schwacher Nukleophile ermöglicht durch [Pd(1‐MeNAP)TFA]2 Präkatalysatoren

Angewandte Chemie, EarlyView.
Bei vielen Pd‐katalysierten Kreuzkupplungen hat sich gezeigt, dass die Katalysatorleistung durch dessen Aktivierung begrenzt wird. Methylnaphthyl (MeNAP)‐Palladiumtrifluoracetat‐Dimere werden als leicht zu lagernde und handhabende Präkatalysatoren vorgestellt, die sich unter Reaktionsbedingungen schnell aktivieren, selbst wenn nur schwach ...
Sourav Manna, Henric F. Janning, Nikolaos V. Tzouras, Jane Anto Simplica Sagayaraj, Fadil Faizal Mannighayil, Angelino Doppiu, Lukas J. Gooßen   +6 more
wiley   +1 more source

Anomere Amide Ermöglichen Aminative Alken‐Aryl‐ und Alken‐Alken‐Kupplungen

Angewandte Chemie
AbstractTrotz der Bedeutung von Kreuzkupplungsreaktionen, bei denen C−N‐Bindungen gebildet werden, stellen aminative Kupplungsansätze, bei denen zwei Fragmente direkt am Heteroatom verknüpft werden, eine selten genutzte retrosynthetische Strategie für den molekularen Aufbau dar.
Colin Stein, Jasper L. Tyler, Julius Wiener, Florian Boser, Constantin G. Daniliuc, Frank Glorius   +5 more
openaire   +1 more source

Substrate‐Controlled Enantiodivergence in Ni‐Catalyzed Access to Phosphorylated Oxindoles With Quaternary Stereocenters

Angewandte Chemie, EarlyView.
An efficient, enantiodivergent synthesis of phosphorylated oxindoles with quaternary stereocenters is achieved via a nickel‐catalyzed intermolecular Heck‐phosphorylation cascade. Employing a single chiral catalyst, either product enantiomer is selectively accessed simply by changing the alkene leaving group. DFT calculations trace this stereodivergence
Haimeng Zhu, Lewen Wang, Shihui Luo, Xinglong Zhang, Jun (Joelle) Wang   +4 more
wiley   +2 more sources

Phenylseleno trifluoromethoxylation of alkenes

Beilstein Journal of Organic Chemistry
Trifluoromethoxylated molecules and selenylated compounds find a wide range of interesting applications, but separately. In order to combine the potential of these two motifs and to propose a new class of compounds, we have developed an electrophilic phenylseleno trifluoromethoxylation of alkenes, which leads to β-selenylated trifluoromethoxylated ...
Clément Delobel, Armen Panossian, Gilles Hanquet, Frédéric R Leroux, Fabien Toulgoat, Thierry Billard   +5 more
openaire   +3 more sources

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

Consequences of Medium‐Pore Zeolite Constraints for Alkene Cracking—The Case of n‐Pentene

Angewandte Chemie, EarlyView.
Alkene cracking in medium‐pore zeolites is governed by a balance of enthalpic and entropic effects. Intrinsic barriers are quantified and shown to be lower than for alkanes due to stabilization of carbenium‐ion‐like transition states. Confinement and extra‐framework aluminum modulate reactivity by tuning transition‐state energetics, providing a ...
Ruixue Zhao, Stefan Schallmoser, Gary L. Haller, Maricruz Sanchez‐Sanchez, Johannes A. Lercher   +4 more
wiley   +1 more source

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

Photocatalytic Transfer Hydrogenation Using Plastic Hydrolysates as Hydrogen Donor

Angewandte Chemie, EarlyView.
Plastic waste is transformed into functional amines via solar‐driven transfer hydrogenation. Soluble monomers from acid hydrolysis of waste polymers serve as a hydrogen (electron/proton)donors in the selective reduction of nitroarenes using a visible light active photocatalyst consisting of cobalt promoted molybdenum disulfide integrated in cyanamide ...
Papa K. Kwarteng, Afreen H. Naceruddin, Erwin Reisner   +2 more
wiley   +1 more source

Direct δ‐Lactone Synthesis From Free Alcohols via Photoinduced δ‐C(sp3)–H Carbonylation in Flow

Angewandte Chemie, EarlyView.
Herein, we have developed a photo‐flow platform for the δ‐C(sp3)─H carbonylative lactonization of free alcohols with carbon monoxide. The transformation integrates alkoxyl radical generation, selective 1,5‐HAT, CO incorporation, and radical–polar crossover to enable direct access to δ‐lactones from simple alcohol precursors.
Prakash Chandra Tiwari, Runkang Liu, Timothy Noël   +2 more
wiley   +2 more sources