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61.
Marie‐Laure Louillat‐Habermeyer Rongwei Jin Prof. Dr. Frederic W. Patureau 《Angewandte Chemie (International ed. in English)》2015,54(13):4102-4104
A method was developed for the direct dehydrogenative construction of C? N bonds between unprotected phenols and a series of cyclic anilines without resorting to any kind of metal activation of either substrate and without the use of halides. The resulting process relies on the exclusively organic activation of molecular oxygen and the subsequent oxidation of the aniline substrate. This allows the coupling of ubiquitous phenols, thus furnishing aminophenols through an atom‐economical and most sustainable dehydrogenative amination method. This new reactivity, which relies on the intrinsic organic reactivity of cumene in what can be seen as a modified Hock activation process of oxygen, is expected to have a large impact on the formation of C? N bonds in organic synthesis. 相似文献
62.
Poineau F Malliakas CD Weck PF Scott BL Johnstone EV Forster PM Kim E Kanatzidis MG Czerwinski KR Sattelberger AP 《Journal of the American Chemical Society》2011,133(23):8814-8817
Technetium dichloride has been discovered. It was synthesized from the elements and characterized by several physical techniques, including single crystal X-ray diffraction. In the solid state, technetium dichloride exhibits a new structure type consisting of infinite chains of face sharing [Tc(2)Cl(8)] rectangular prisms that are packed in a commensurate supercell. The metal-metal separation in the prisms is 2.127(2) ?, a distance consistent with the presence of a Tc≡Tc triple bond that is also supported by electronic structure calculations. 相似文献
63.
A Rh catalyzed, no-chelate-assisted C-H activation/oxidative olefination reaction of bromoarenes has been discovered, in which the latter ones seem to act as a substrate, terminal oxidant, and catalyst modifier. 相似文献
64.
Substituted 2-bromobenzaldehydes were synthesized from benzaldehydes using a three-step sequence involving a selective palladium-catalyzed ortho-bromination as the key step. O-Methyloxime serves as a directing group in this reaction. A rapid deprotection of substituted 2-bromobenzaldoximes afforded substituted 2-bromobenzaldehydes with good overall yields. 相似文献
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68.
Frederic Poineau Erik V. Johnstone Alfred P. Sattelberger Kenneth R. Czerwinski 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):235-239
Technetium tetrachloride and β-TcCl3, synthesized from the reaction of Tc metal and Cl2(g) in sealed tubes, were characterized by X-ray absorption fine structure spectroscopy. Extended X-ray absorption fine structure (EXAFS) spectroscopy measurements are in good agreement with the X-ray diffraction structures of the two compounds. For TcCl4, the absorbing Tc atom is surrounded by Cl atoms at 2.34(2) Å and Tc atoms at 3.66(4) Å. For β-TcCl3, the absorbing Tc atom is surrounded by Cl atoms at 2.40(2) Å and Tc atoms at 2.81(3), 3.66(4) and 5.71(6) Å. EXAFS spectroscopy indicates that the TcCl4 and β-TcCl3 samples obtained by sealed tube reactions are single phase. The X-ray absorption near edge structure spectra of TcCl4 and β-TcCl3 were recorded; the positions of the Tc K-edges of β-TcCl3 (21,050.5 eV) and TcCl4 (21,053.0 eV) are compared to the ones measured for α-TcCl3 (21,051.0 eV) and TcCl2 (21,048.8 eV). A correlation between the positions of the Tc K-edges and the oxidation state of the Tc atom in technetium binary chlorides was determined. 相似文献
69.
Ohne Zusammenfassung 相似文献
70.
Frederic Paik Schoenberg 《Annals of the Institute of Statistical Mathematics》2002,54(2):445-457
The process obtained by rescaling a homogeneous Poisson process by the maximum likelihood estimate of its intensity is shown to have surprisingly strong self-correcting behavior. Formulas for the conditional intensity and moments of the rescaled Poisson process are derived, and its behavior is demonstrated using simulations. Relationships to the Brownian bridge are explored, and implications for point process residual analysis are discussed. 相似文献