The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Chris J Pickard - One of the best experts on this subject based on the ideXlab platform.
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high pressure phases of group ii Difluorides polymorphism and superionicity
Physical Review B, 2017Co-Authors: Joseph R Nelson, R J Needs, Chris J PickardAbstract:We investigate the high-pressure behavior of beryllium, magnesium, and calcium Difluorides using ab initio random structure searching and density functional theory (DFT) calculations, over the pressure range $0--70$ GPa. Beryllium fluoride exhibits extensive polymorphism at low pressures, and we find two new phases for this compound---the silica moganite and ${\mathrm{CaCl}}_{2}$ structures---which are stable over the wide pressure range $12--57$ GPa. For magnesium fluoride, our searching results show that the orthorhombic ``O-I'' ${\mathrm{TiO}}_{2}$ structure $(Pbca,Z=8)$ is stable for this compound between 40 and 44 GPa. Our searches find no new phases at the static-lattice level for calcium difluoride between 0 and 70 GPa; however, a phase with $P\overline{6}2m$ symmetry is close to stability over this pressure range, and our calculations predict that this phase is stabilized at high temperature. The $P\overline{6}2m$ structure exhibits an unstable phonon mode at large volumes which may signal a transition to a superionic state at high temperatures. The group-II Difluorides are isoelectronic to a number of other ${\mathrm{AB}}_{2}$-type compounds such as ${\mathrm{SiO}}_{2}$ and ${\mathrm{TiO}}_{2}$, and we discuss our results in light of these similarities.
Frank M Prozonic - One of the best experts on this subject based on the ideXlab platform.
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bis 2 methoxyethyl aminosulfur trifluoride a new broad spectrum deoxofluorinating agent with enhanced thermal stability
Chemical Communications, 1999Co-Authors: Gauri Sankar Lal, Guido Peter Pez, Reno Joseph Pesaresi, Frank M ProzonicAbstract:Bis(2-methoxyethyl)aminosulfur trifluoride (Deoxo-FluorTM) is effective for the conversion of alcohols to alkyl fluorides, aldehydes/ketones to the corresponding gem-Difluorides and also for the transformation of carboxylic acids to their trifluoromethyl derivatives; it is a less thermally sensitive, broader-spectrum alternative to the traditional dialkylaminosulfur trifluoride (DAST) deoxofluorination reagents.
Gauri Sankar Lal - One of the best experts on this subject based on the ideXlab platform.
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fluorination of thiocarbonyl compounds with bis 2 methoxyethyl aminosulfur trifluoride deoxo fluor reagent a facile synthesis of gem Difluorides
ChemInform, 2000Co-Authors: Gauri Sankar Lal, Elyse Lobach, Ann EvansAbstract:A variety of thiocarbonyl derivatives (thioketone, thioester, thioamide, dithioester, and dithiocarbamate) were converted to the corresponding gem-Difluorides in excellent yields on reaction with the fluorinating agent, bis(2-methoxyethyl)aminosulfur trifluoride, in the presence of SbCl3.
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bis 2 methoxyethyl aminosulfur trifluoride a new broad spectrum deoxofluorinating agent with enhanced thermal stability
Chemical Communications, 1999Co-Authors: Gauri Sankar Lal, Guido Peter Pez, Reno Joseph Pesaresi, Frank M ProzonicAbstract:Bis(2-methoxyethyl)aminosulfur trifluoride (Deoxo-FluorTM) is effective for the conversion of alcohols to alkyl fluorides, aldehydes/ketones to the corresponding gem-Difluorides and also for the transformation of carboxylic acids to their trifluoromethyl derivatives; it is a less thermally sensitive, broader-spectrum alternative to the traditional dialkylaminosulfur trifluoride (DAST) deoxofluorination reagents.
Thomas Huhn - One of the best experts on this subject based on the ideXlab platform.
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Titanocene Difluorides with Improved Cytotoxic Activity
Inorganic Chemistry, 2010Co-Authors: Silvia Eger, James Claffey, Timo A. Immel, Matthias Tacke, Ulrich Groth, Helge Müller-bunz, Thomas HuhnAbstract:Titanocene Difluorides can be obtained by halide metathesis of the respective titanocene dichlorides with trimethyltin fluoride (Me3SnF), giving access to a new class of cytotoxic active substances. Furthermore, an improved method for the synthesis of diaryl-substituted titanocene dichlorides is presented.
Shuji Yasuike - One of the best experts on this subject based on the ideXlab platform.
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palladium catalyzed c h arylation of benzofurans with triarylantimony Difluorides for the synthesis of 2 arylbenzofurans
Molecules, 2020Co-Authors: Yuki Kitamura, Yuki Murata, Mizuki Iwai, Mio Matsumura, Shuji YasuikeAbstract:Pd-catalyzed regioselective C-H arylation is a useful tool for the chemical modification of aromatic heterocycles and 2-arylbenzofuran derivatives are of interest as biologically active substances. Herein, the reaction of triarylantimony Difluorides with benzofurans under aerobic conditions in 1,2-DCE, using 5 mol% Pd (OAc)2 and 2 eq. of CuCl2 at 80 °C, produced a variety of 2-arylbenzofurans in moderate-to-high yields. The reaction is sensitive to the electronic nature of the substituents on the benzene ring of the triarylantimony Difluorides: an electron-donating group showed higher reactivity than an electron-withdrawing group. Single crystal X-ray analysis of tri(p-methylphenyl) antimony difluoride revealed that the central antimony atom exhibits trigonal bipyramidal geometry.
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a versatile synthesis of triarylantimony Difluorides by fluorination of triarylstibanes with nitrosyl tetrafluoroborate and their antitumor activity
Journal of Fluorine Chemistry, 2017Co-Authors: Yuki Kitamura, Yuki Murata, Mio Matsumura, Mizuki Yamada, Naoki Kakusawa, Motohiro Tanaka, Hiroyuki Okabe, Hiroshi Naka, Tohru Obata, Shuji YasuikeAbstract:Abstract Triarylantimony Difluorides were synthesized in moderate to excellent yields by oxidative fluorination of triarylstibanes with nitrosyl tetrafluoroborate (NOBF4) under aerobic conditions. This reaction is the first example of fluorination of trivalent organoantimony compounds using NOBF4 as a fluorinating agent. The triarylantimony Difluorides exhibited good anti-proliferation activity against tumor cell lines. In particular, the IC50 of p-Tol3SbF2 (2c) was the lowest in each cell lines.