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In dimethylsulfoxide, nitric oxide reduces copper(II) to copper(I) in the presence of p-chloroaniline. The resulting copper(I) is determined spectrophotometrically with 2,2′-biquinoline. The reactions are reproducible and the absorbance is proportional to the concentration of nitric oxide over the range 1.8–108 ppm (mg dm?3. Most other atmospheric contaminants are without effect. 相似文献
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Ogoshi S Tomiyasu S Morita M Kurosawa H 《Journal of the American Chemical Society》2002,124(39):11598-11599
In the presence of a catalytic amount of Me(3)SiOTf and palladium(0), the addition of disilane to alpha,beta-unsaturated carbonyl compounds proceeds under very mild conditions via eta(3)-siloxyallylpalladium generated by the reaction of enone, enal, or aromatic aldehyde with palladium and Me(3)SiOTf. 相似文献
87.
Raman spectra of Fe3+ and Pd2+ octaethylporphyrin (OEP) and their α′, β′, γ′, and δ′ deutero derivatives were measured with the 5145, 4880 and 4765 Å lines of an Ar ion laser. Raman bands due to methine-bridge stretching vibrations were assigned and their vibrational amplitudes were calculated from the observed frequency shifts on deuterium substitution of methine-bridge hydrogens. These vibrations correspond to the spin-state sensitive Raman bands of heme proteins. On the basis of symmetry considerations and the observed polarizations, vibrational assignments of other Raman bands were made. 相似文献
88.
Nahomi Sakaguchi Shuji Matsuo Tsutomu Kurisaki Taku Matsuo Hisanobu Wakita 《Research on Chemical Intermediates》2006,32(2):95-101
The photocatalytic degradation of 2-propanol in D2O solution under UV irradiation was investigated. The conversion yield from 2-propanol to acetone was studied by 1H-NMR measurements. The study was carried out to elucidate effects of O2 in the reaction medium and lanthanide ion modification on the TiO2 surface. Under aerobic conditions, acetone formation was clearly increased in comparison with anaerobic conditions. On the
modification of TiO2 with lanthanide ion, the conversion yield decreased with the increase in the ionic radius. Yb3+ ion modification increased the acetone formation by approx. 5% in comparison with the unmodified case. Appreciably large
effects of the counter ion in lanthanide salts were also observed. The role of OH˙ radical formation in the first step of photocatalysis was emphasized in the experimental results. 相似文献
89.
Strategic Utilization of Multifunctional Carbene for Direct Synthesis of Carboxylic–Phosphinic Mixed Anhydride from CO2
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Prof. Dr. Yoichi Hoshimoto Takahiro Asada Dr. Sunit Hazra Takuya Kinoshita Panukorn Sombut Dr. Ravindra Kumar Prof. Dr. Masato Ohashi Prof. Dr. Sensuke Ogoshi 《Angewandte Chemie (International ed. in English)》2016,55(52):16075-16079
Direct synthesis of carboxylic–phosphinic mixed anhydrides has been achieved by treating carbon dioxide with N‐phosphine oxide‐substituted imidazolylidenes (PoxIms) that contain both nucleophilic carbene and electrophilic phosphorus moieties. This novel mixed anhydride was efficiently derivatized into an ester, an amide, and an unsymmetrical ketone via transformation into its corresponding imidazolium salt followed by a dual substitution reaction. The presented work used well‐designed multifunctional carbene reagents to establish a novel utility for carbon dioxide in organic synthesis. 相似文献
90.
Dr. Kenichi Kato Prof. Dr. Shixin Fa Prof. Dr. Tomoki Ogoshi 《Angewandte Chemie (International ed. in English)》2023,62(47):e202308316
Pillar[n]arenes are symmetrical macrocyclic compounds composed of benzene panels with para-methylene linkages. Each panel usually exhibits planar chirality and prefers chirality-aligned states. Because of this feature, pillar[n]arenes are attractive scaffolds for chiroptical materials that are easy to prepare and optically resolve and show intense circular dichroism (CD) signals. In addition, rotation of the panels endows the chirality of pillar[n]arenes with a dynamic nature. The chirality in tubular oligomers and supramolecular assemblies sometimes show time- and procedure-dependent alignment phenomena. Furthermore, the CD signals of some pillar[n]arenes respond to the addition of chiral guests when their dynamic chirality is coupled with host–guest properties. By using diastereomeric pillar[n]arenes with additional chiral structures, the response can also be caused by achiral guests and changes of the environment, providing molecular sensors. 相似文献