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11.
Infrared fluorescence observed after exciting to ν6 (ν=1) of CD3H with a Q-switched CO2 laser yields the exponential deactivation rate constant of 0.84 ms?1 torr?1. Rate constants for deactivation of CD3H by rare gases vary from 1.4 (for He) to 0.029 (for Xe) ms?1 torr?1. 相似文献
12.
P.A. Bates E.J. Ditzel M.P. Hartshorn Huong Tuong Ing K.E. Richards W.T. Robinson 《Tetrahedron letters》1981,22(24):2325-2328
Dinitration of 2,4,5-tribromo-3,6-dimethylphenol(1) gives either the tribromodinitro-compound(2) or its acyloin rearrangement product(3), depending on the reaction conditions: X-ray crystal structure analyses are reported for compounds (2) and (3). 相似文献
13.
A new protocol for synthesis of 2-heterocylylacetic acid derivatives involving conjugate addition of allyl mercaptan to an acrylate containing a tethered olefinic site followed by RCM (ring-closing metathesis) is described. In this series, sulfanyl derivatives were unreactive, while sulfoxide and sulfone analogues provided the corresponding thiazocines in fair to excellent yields. Use of the sulfoxide oxidation state as a protecting group for sulfides inert to RCM is demonstrated also. Thus, oxidation of sulfide 9 [N-allyl-N-[2-(allylthio)-4-(1H-indol-1-yl)-4-oxobutyl]-4-methylbenzenesulfonamide] followed by cyclization yielded the corresponding thiazocine sulfoxide 12. Deprotection (deoxygenation) of 12 was accomplished using Lawesson's reagent, producing 1-[[4-[4-(methylphenyl)sulfonyl]-3,4,5,8-tetrahydro-2H-1,4-thiazocin-2-yl]acetyl]-1H-indole (21) in 67% unoptimized yield. 相似文献
14.
Four new sulfur-containing compounds based on pyridine, benzene, 1,8-naphthyridine and 1,10-phenanthroline have been synthesized. These molecules have been incorporated into a polymeric matrix as neutral carriers and evaluated as silver sensors. Two of the compounds (pyridine and benzene) show high selectivity for Ag(+). The sensor with the pyridine-based compound, in particular, shows near-Nernstian response and good sensitivity towards Ag(+) with a short response time (<10s), making it ideal for use in flow analysis. 相似文献
15.
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17.
The moment functions of H+2 are computed for internuclear distances up to 5a0 from the dipole osciliator strengths. 相似文献
18.
Doris J. Bates Myron Rosenblum Sari B. Samuels 《Journal of organometallic chemistry》1981,209(3):C55-C59
CpFe(CO)2[C(OEt)R]BF4 complexes can be prepared by reaction of CpFe(CO)2(isobutylene)BF4 with monoalkylated acetylenes in methylene chloride/ethanol solutions. Methyl propiolate yields methyl trans-2-ethoxy-acrylate, in a reaction catalytic in CpFe(CO)2(isobutylene)BF4, and internal acetylenes can be transformed to CpFe(CO)2(vinyl ether)BF4 complexes. 相似文献
19.
Earlier work by Lindenbaum and Boyd has demonstrated the important role of hydrophobic interactions involving the water solvent in determining the osmotic coefficients and properties of aqueous solutions of the tetraalkylammonium halides. Osmotic coefficients of solutions of tetramethyl-, tetraethyl-, tetrapropyl-, and tetrabutylammonium bromides in the more highly structured solvent D2O have now been determined by the gravimetric isopiestic method, using reference solutions of NaCl in D2O. The data were fitted to the Rush-Johnson and Pitzer equations. Satisfactory agreement with the results for aqueous solutions at comparable concentrations indicates that the solution chemistry of these quaternary ammonium bromides is not highly dependent on the degree of structure of the pure solvents. Supplementary data for mixtures of Me4NBr with Et4NBr, Pr4NBr, or Bu4NBr in both H2O and D2O are consistent with this conclusion.On leave 1980–82 from Banaras Hindu University, India 相似文献
20.
Resonance Raman and infrared absorption spectra of ClO3 radicals have been observed from measurements of crystalline NaClO3 irradiated at 77 K with 1.5 MeV electrons. The ClO3 radicals occupy two sets of nonequivalent sites; radicals at one site are observed from resonance scattering using 6328 Å excitation while those at the other site are observed from resonance scattering with 5145 Å excitation. The red sensitive radicals decompose at 77 K with a half-life of ≈29 min while the green sensitive radicals are more stable at this temperature. 相似文献