Results 51 to 60 of about 37,807 (249)

Aziridinierung eines einzelnen Kohlenstoffatoms in Alkenen mittels Energietransferkatalyse

Angewandte Chemie, EarlyView.
Im Gegensatz zur traditionellen Alken‐Aziridinierung über (formalen) Nitren‐Transfer berichten wir hier über eine Strategie zur intermolekularen Aziridinierung eines einzelnen Alken‐Kohlenstoffatoms bei zusätzlicher Funktionalisierung der anderen Position. Durch Energietransfer‐ (EnT‐)Katalyse werden Alkenylboronate und ‐silane in reaktive Intermediate
Fritz Paulus, Corinna Heusel, Felix H. Wessels, Bünyamin Sikora, Maik G. Niedziella, Kilian van der Beck, Constantin G. Daniliuc, Frank Glorius   +7 more
wiley   +1 more source

Photochemistry of 3H-furo[3,4-c]pyrazoles and 3H-thieno[3,4-c] pyrazoles

, 2013
The first examples of 3H-furo [3,4-c]pyrazoles and 3H-thieno[3,4-c]pyrazoles were prepared in an attempt to isolate examples of cyclopropane-fused thiophenes and furans.
Payne, Alan
core   +1 more source

Synthesis of 2H-furo[2,3-c]pyrazole ring systems through silver(I) ion-mediated ring-closure reaction

Beilstein Journal of Organic Chemistry, 2019
Fused pyrazole ring systems are common structural motifs of numerous pharmaceutically important compounds. Nevertheless, access to derivatives of the aromatic 2H-furo[2,3-c]pyrazole ring system is still quite limited, and their chemistry and functional ...
Vaida Milišiūnaitė, Rūta Paulavičiūtė, Eglė Arbačiauskienė, Vytas Martynaitis, Wolfgang Holzer, Algirdas Šačkus   +5 more
doaj   +1 more source

Revisiting the Chemistry of Vinylpyrazoles: Properties, Synthesis, and Reactivity

Molecules, 2022
Vinylpyrazoles, also known as pyrazolyl olefins, are interesting motifs in organic chemistry but have been overlooked. This review describes the properties and synthetic routes of vinylpyrazoles and highlights their versatility as building blocks for the
Vera L. M. Silva, Artur M. S. Silva
doaj   +1 more source

Regioselective synthesis of 1-aryl-3,4-substituted/annulated-5-(methylthio)pyrazoles and 1-aryl-3-(methylthio)-4,5-substituted/annulated pyrazoles

, 2005
Highly efficient and regioselective synthesis of 1-aryl-3,4-substituted/annulated-5-(methylthio)pyrazoles and 1-aryl-3-(methylthio)-4,5-substituted/annulated pyrazoles has been reported via cyclocondensation of arylhydrazines with either α-oxoketene ...
Peruncheralathan, S., Ila, H., Junjappa, H., Khan, T. A.   +3 more
core   +1 more source

Aziridination of a Single Carbon Atom in Alkenes via Energy Transfer Catalysis

Angewandte Chemie International Edition, EarlyView.
Contrary to traditional alkene aziridination via (formal) nitrene transfer, we herein report a strategy that achieves intermolecular aziridination of a single alkene carbon atom and installs an additional group at the other. Enabled by metal‐free energy transfer (EnT) catalysis, alkenyl boronates and silanes are transformed into reactive intermediates ...
Fritz Paulus, Corinna Heusel, Felix H. Wessels, Bünyamin Sikora, Maik G. Niedziella, Kilian van der Beck, Constantin G. Daniliuc, Frank Glorius   +7 more
wiley   +1 more source

Temperature-Controlled Divergent Synthesis of Pyrazoles and 1-Tosyl-1H-pyrazoles under Transition-Metal-Catalyst- and Oxidant-Free Conditions

Molecules
Herein, a general and practical temperature-controlled approach for the divergent synthesis of pyrazoles and 1-tosyl-1H-pyrazoles via electrophilic cyclization in the absence of transition-metal catalysts and oxidants was developed.
Kai Wang, Wenjing Xu, Chengcai Xia, Xianting Cao   +3 more
doaj   +1 more source

An Approach to 1,1-Disubstituted Pyrazolylcyclopropane Building Blocks

SynOpen, 2017
An approach to isomeric 1,1-disubstituted pyrazolylcyclopropanes that relies on lithium diisopropylamide (LDA) mediated bis-alkylation­ of the corresponding pyrazolylacetonitriles is developed.
Pavel S. Nosik, Oleksiy S. Artamonov, Sergey V. Ryabukhin, Oleksandr O. Grygorenko   +3 more
doaj   +1 more source

Shedding Light on Synthetic Autocatalysis: From Conventional Closed‐Shell Chemistries to Overlooked Open‐Shell Occurrences

Chemistry – A European Journal, EarlyView.
Why add another catalyst when the product itself holds the power to catalyze its own formation? Autocatalysis in synthetic chemistry enhances reaction efficiency and uncovers novel catalytic behavior across both closed‐shell and open‐shell systems, expanding reactivity and enabling innovative design strategies.
Jaspreet Kaur, Joshua P. Barham
wiley   +1 more source

The pyrazolo[4,3-c]pyrazole core as a novel and versatile scaffold for developing dual DYRK1A-CLK1 inhibitors targeting key processes of Alzheimer's disease pathology

European Journal of Medicinal Chemistry Reports
In the current study, we designed, synthesized, and characterized a series of substituted pyrazolo[4,3-c]pyrazoles. These novel compounds were evaluated in vitro for their inhibitory activity over a panel of protein kinases to determine their potential ...
Vaia-Argyro Bakalakou, Barbara Mavroidi, Amalia D. Kalampaliki, Béatrice Josselin, Stéphane Bach, Alexios-Leandros Skaltsounis, Panagiotis Marakos, Nicole Pouli, Maria Pelecanou, Vassilios Myrianthopoulos, Sandrine Ruchaud, Ioannis K. Kostakis   +11 more
doaj   +1 more source