نتایج جستجو برای: fluorination treatment

تعداد نتایج: 1395580  

Journal: :ACS catalysis 2015
Kenichi Hiramatsu Takashi Honjo Vivek Rauniyar F Dean Toste

Stereoselective synthesis of two fluorine-bearing drug-like scaffolds, dihydroquinazolone and benzooxazinone, has been accomplished through asymmetric fluorocyclization reactions initiated by the fluorination process. The reaction employs double axially chiral anionic phase-transfer catalysts to achieve high diastereo- and enantioselectivities, and a wide range of fluorine-containing dihydroqui...

Journal: :Molecules 2017
Taras M Sokolenko Maya I Dronkina Emmanuel Magnier Lev M Yagupolskii Yurii L Yagupolskii

The "chlorination/fluorination" technique for aliphatic trifluoromethyl ether synthesis was investigated and a range of products with various functional groups was prepared. The results were compared with oxidative desulfurization-fluorination of xanthates with the same structure.

2004
L. K. Pan Y. K. Ee C. Q. Sun G. Q. Yu B. K. Tay

The effect of plasma fluorination on the band gap, 2p core-level energy, and the dielectric behavior of porous silicon ~PS! prepared under constant conditions has been examined using Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, photoluminescence, and reflection. It has been found that with increasing extent of fluorination, the band gap expands, and the 2p level an...

2015
Bin Yin Shinsuke Inagi Toshio Fuchigami

Anodic fluorination of dithioacetals bearing electron-withdrawing ester, acetyl, amide, and nitrile groups at their α-positions was comparatively studied using various supporting poly(HF) salts like Et3N·nHF (n = 3-5) and Et4NF·nHF (n = 3-5). In the former two cases, the corresponding α-fluorination products or fluorodesulfurization products were obtained selectively depending on supporting pol...

Journal: :Journal of Synthetic Organic Chemistry, Japan 1958

Journal: :Angewandte Chemie 2013
Theresa Liang Constanze N Neumann Tobias Ritter

Over the past decade, the most significant, conceptual advances in the field of fluorination were enabled most prominently by organo- and transition-metal catalysis. The most challenging transformation remains the formation of the parent C-F bond, primarily as a consequence of the high hydration energy of fluoride, strong metal-fluorine bonds, and highly polarized bonds to fluorine. Most fluori...

2018
Shunsuke Kuribayashi Tomoyuki Kurioka Shinsuke Inagi Ho-Jung Lu Biing-Jiun Uang Toshio Fuchigami

We herein report that the regioselective anodic fluorination of S-alkyl benzothioate and its derivatives in various aprotic solvents using Et3N·nHF (n = 3-5) and Et4NF·nHF (n = 3-5) as supporting electrolyte and a fluorine source successfully provided the corresponding α-fluorinated products in moderate yields. Dichloromethane containing Et4NF·4HF was found to be the most suitable combination a...

Journal: :Physical chemistry chemical physics : PCCP 2012
Jing Zeng Ke-Qiu Chen Chang Q Sun

By applying the nonequilibrium Green's functions and the density-functional theory, we investigate the electronic structures and transport properties of fluorinated zigzag-edged boron nitride nanoribbons. The results show that the transition between half-metal and semiconductor in zigzag-edged boron nitride nanoribbons can be realized by fluorination at different sites or by the change of the f...

2014
Kazutaka Shibatomi Takuya Okimi Yoshiyuki Abe Akira Narayama Nami Nakamura Seiji Iwasa

In a previous study it was shown that the enantioselective α-fluorination of racemic α-chloroaldehydes with a chiral organocatalyst yielded the corresponding α-chloro-α-fluoroaldehydes with high enantioselectivity. It was also revealed that kinetic resolution of the starting aldehydes was involved in this asymmetric fluorination. This paper describes the determination of the absolute stereochem...

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