Results 41 to 50 of about 596,435 (207)

Transition‐Metal‐Free Cleavage of CO [PDF]

Chemistry – A European Journal, 2017
AbstractTertiary silane 1H, 2‐[(diphenylsilyl)methyl]‐6‐methylpyridine, reacts with tris(pentafluorophenyl)borane (BCF) to form the intramolecular pyridine‐stabilized silylium 1+‐HBCF. The corresponding 2‐[(diphenylsilyl)methyl]pyridine, lacking the methyl‐group on the pyridine ring, forms classic N(py)→B adduct 2H‐BCF featuring an intact silane Si−H ...
Devillard, Marc, De bruin, Bas, Siegler, Maxime, Van der vlugt, J.   +3 more
openaire   +5 more sources

Metal-Free Cascade Formation of C–C and C–N Bond for the Construction of 3-Cyano-2-Pyridones with Insecticidal Properties

Molecules
A straightforward and efficient methodology has been developed for the synthesis of 3-cyano-2-pyridones via the C–C and C–N bond formation processes. A total of 51 diverse 3-cyano-2-pyridone derivatives were obtained in moderate to excellent yields. This
Yao Tang, Nvjiang Wu, Junyu Xu, Xiaopo Zhang, Youbin Li, Xuesong Wang   +5 more
doaj   +1 more source

Recent Advances in Transition-Metal-Free Late-Stage C-H and N-H Arylation of Heteroarenes Using Diaryliodonium Salts

Pharmaceuticals, 2021
Transition-metal-free direct arylation of C-H or N-H bonds is one of the key emerging methodologies that is currently attracting tremendous attention. Diaryliodonium salts serve as a stepping stone on the way to alternative environmentally friendly and ...
Thierry Besson, Corinne Fruit
doaj   +1 more source

Direct Formation of Supermassive Black Holes via Multi-Scale Gas Inflows in Galaxy Mergers [PDF]

, 2009
Observations of distant bright quasars suggest that billion solar mass supermassive black holes (SMBHs) were already in place less than a billion years after the Big Bang.
A Escala, A. Escala, D Eisenstein, F Governato, F Walter, FI Pelupessy, G Lodato, H Mo, J Regan, J Shlosman, J Wise, JL Johnson, K Omukai, L Mayer, L. Mayer, M Begelman, M Milosavljevic, M Spaans, M Volonteri, M Volonteri, MA Alvarez, MG Haehnelt, P Madau, R Levine, RS Klessen, S Kazantzidis, S. Callegari, S. Kazantzidis, SL Shapiro, V Bromm, X Fan, Y Li, Z Haiman   +32 more
core   +3 more sources

Reactive Plasma N-Doping of Amorphous Carbon Electrodes: Decoupling Disorder and Chemical Effects on Capacitive and Electrocatalytic Performance

Frontiers in Chemistry, 2020
Nitrogen-free amorphous carbon thin films prepared via sputtering followed by graphitization, were used as precursor materials for the creation of N-doped carbon electrodes with varying degrees of amorphization.
Md. Khairul Hoque, James A. Behan, James Creel, James G. Lunney, Tatiana S. Perova, Paula E. Colavita   +5 more
doaj   +1 more source

Metal-Free Fabrication of Fused Silica Extended Nanofluidic Channel to Remove Artifacts in Chemical Analysis

Micromachines, 2021
In microfluidics, especially in nanofluidics, nanochannels with functionalized surfaces have recently attracted attention for use as a new tool for the investigation of chemical reaction fields.
Kyojiro Morikawa, Ryoichi Ohta, Kazuma Mawatari, Takehiko Kitamori   +3 more
doaj   +1 more source

The role of hydrogen in room-temperature ferromagnetism at graphite surfaces

, 2010
We present a x-ray dichroism study of graphite surfaces that addresses the origin and magnitude of ferromagnetism in metal-free carbon. We find that, in addition to carbon $\pi$ states, also hydrogen-mediated electronic states exhibit a net spin ...
, A Setzer, D Spemann, E Arenholz, H Ohldag, M Rothermel, P Esquinazi, Stöhr J, Stöhr J, T Butz   +9 more
core   +2 more sources

Octakis(dodecyl)phthalocyanines: Influence of Peripheral versus Non-Peripheral Substitution on Synthetic Routes, Spectroscopy and Electrochemical Behaviour

Molecules, 2022
Non-peripherally octakis-substituted phthalocyanines (npPc’s), MPc(C12H25)8 with M = 2H (3) or Zn (4), as well as peripherally octakis-substituted phthalocyanines (pPc’s) with M = Zn (6), Mg (7) and 2H (8), were synthesized by cyclotetramerization of 3,6-
Glendin Swart, Eleanor Fourie, Jannie C. Swarts   +2 more
doaj   +1 more source

Nucleosynthesis in Metal-Free and Metal-Poor Stars

, 2008
There have been a number of important recent developments in theoretical and observational studies of nucleosynthesis, especially regarding nucleosynthetic sources at low metallicities.
Qian, Yong-Zhong
core   +1 more source

Intramolecular Oxidative Diaryl Coupling of Tetrasubstituted Diphenylamines for the Preparation of Bis(trifluoromethyl) Dimethyl Carbazoles

SynOpen, 2021
Synthetic preparation of carbazoles can be challenging, requiring ring-building strategies and/or precious metal catalysts. Presented herein is a method for the preparation of carbazoles with the use of inexpensive and reliable hypervalent iodine ...
Addison M. Duda, Michael T. Giurini, Jason G. Gillmore, Thomas F. Guarr   +3 more
doaj   +1 more source