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31.
Florian Ritter Dr. Lukas John Dr. Tobias Schindler Julian P. Schroers Simon Teeuwen Dr. Michael E. Tauchert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(59):13436-13444
The dative Pd→B interaction in a series of RDPBR’ Pd0 and PdII complexes (RDPBR’=(o-PR2C6H4)2BR’, diphosphinoborane) was analyzed using XRD, 11B NMR spectroscopy and NBO/NLMO calculations. The borane acceptor discriminates between the oxidation state PdII and Pd0, stabilizing the latter. Reaction of lithium amides with [(RDPBR’)PdII(4-NO2C6H4)I] chemoselectively yields the C−N coupling product. DFT modelling indicates no significant impact of PdII→B coordination on the inner-sphere reductive elimination rate. 相似文献
32.
Effective field theories of the strong interactions based on the approximate chiral symmetry of QCD provide a model-independent
approach to low-energy hadron physics. We give a brief introduction to mesonic and baryonic chiral perturbation theory and
discuss a number of applications. We also consider the effective field theory including vector and axial-vector mesons. 相似文献
33.
Sutorik AC Patschke R Schindler J Kannewurf CR Kanatzidis MG 《Chemistry (Weinheim an der Bergstrasse, Germany)》2000,6(9):1601-1607
Mixed S2-/S1- oxidation states have been discovered in the new quaternary compound K6Cu12U2S15. Synthesized from the reaction of Cu and U in a molten alkali metal/polysulfide flux, the compound crystallizes in the cubic space group Ia3d (no. 230) with a = 18.642(7) angstroms. Its complex structure is built from [US6] octahedra connected into one-dimensional columns with [CuS3] trigonal planar units, which also serve as inter-column connection points for the extended three-dimensional structure. Magnetic susceptibility measurements reveal Curie-Weiss paramagnetic behavior at temperatures above 100 K with a microeff of 2.96 microB per formula. This corresponds to 2.1 microB per U atom, and it is insufficient to distinguish between U4+ and U5+ paramagnetic ions. The conductivity of hot-pressed polycrystalline pellets is approximately 1500 Scm(-1) at room temperature, and increasing conductivity with decreasing temperature is observed, indicating metallic behavior for the material. Small and positive values for the material's thermopower (3-4 microVK(-1) from 100-300 K) also confirm p-type metallic behavior. 相似文献
34.
C. J. Baddeley A. F. Lee R. M. Lambert T. Gie el O. Schaff V. Fernandez K. -M. Schindler A. Theobald C. J. Hirschmugl R. Lindsay A. M. Bradshaw D. P. Woodruff 《Surface science》1998,400(1-3):166-175
A quantitative structure determination of a newly discovered (2×2) adsorption phase of acetylene chemisorbed on Pd{111} has been performed by scanned-energy mode photoelectron diffraction: this phase corresponds to the threshold coverage for the catalytic conversion of acetylene to benzene. The carbon atoms in the C2H2 molecule are located almost over bridge sites with a C–C bond length of 1.34+0.10 Å, the centre of the molecule being positioned almost over a hollow site. Of the two hollow sites the hcp site (directly above a second layer Pd atom) is favoured, particularly by a subset of the data most sensitive to this aspect of the structure, but the full analysis indicates that the fcc site (above a third layer Pd atom) cannot formally be excluded. The adsorption site adopted by acetylene in the higher coverage
phase on Pd{111} is essentially identical. This is the dominant structure in the coverage regime which is catalytically active for the conversion of acetylene to benzene. The implications of these findings for acetylene coupling reactions over Pd{111} are discussed. 相似文献
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37.
Othmar Schindler Peter Niklaus Urs Stauss Hans Peter Hrter 《Helvetica chimica acta》1976,59(8):2704-2710
Photochemical cyclization of 1-[3-(chloroacetylamino)propyl]-3-methyl-indole . Photochemical cyclization of 1-[3-(chloroacetylamino)propyl]-3-methyl-indole involving loss of HCl leads to the three isomers 2, 3 and 4 , the structures of which have been determined by physical and chemical methods. 相似文献
38.
J. G. Schindler und M. v. Gülich 《Fresenius' Journal of Analytical Chemistry》1980,303(5):414-415
Ohne Zusammenfassung
A long-lasting pO2 electrode with stable measuring properties provided by an anodic Ag+ barrier相似文献
39.
A. Schindler Y. M. Hibionada C. G. Pitt 《Journal of polymer science. Part A, Polymer chemistry》1982,20(2):319-326
The effect of initiation of ?-caprolactone polymerization with mono- and polyfunctional alcohols was investigated. The resulting linear and starshaped polymers were characterized by measurement of the molecular weight and molecular weight distribution. The polymerizations were characterized by (1) rapid initiation, (2) invariance of the number of growing chains corresponding to the amount of initiator, and (3) a dominant role played by ester interchange reactions. 相似文献
40.