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31.
Zusammenfassung Salicylsäurechlorid (1) reagiert mit Campherimin ·HCl bzw. Campheranil oder mit Aldazinen zu Derivaten des 1,3-Benzoxazin-4-ons.
Salicoyl chloride reacts with camphorimine hydrochloride and camphoranile or with aldazines to give derivatives of 1.3-benzoxazin-4-ones.相似文献
32.
Gert Eckhardt 《Journal of mass spectrometry : JMS》1979,14(1):31-35
Due to neighbouring group effects the behaviour under electron impact of amino ethers of the type RO(CH2)nNR1R2 is distinctly different from that of both simple ethers and amines. In addition to α-cleavages two further primary fragmentations can often be observed, one leading to [M–aldehyde]+. or [M–ketone]+. ions, the other (with n≥3) giving [M–R]+ ions. Both processes involve hydrogen rearrangements which were investigated by means of deuterium labelling. Their importance is strongly dependent upon the nature of the substituents R, R1, R2 and upon the length (n) of the carbon chain between the heteroatoms. This dependence can easily be explained by the fragmentation mechanisms put forward. 相似文献
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Dr. Nicole M. G. Franssen Dr. Bernd Ensing Maruti Hegde Prof. Dr. Theo J. Dingemans Ben Norder Prof. Dr. Stephen J. Picken Gert O. R. Alberda van Ekenstein Dr. Ernst R. H. van Eck Dr. Johannes A. A. W. Elemans Mark Vis Prof. Dr. Joost N. H. Reek Prof. Dr. Bas de Bruin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(35):11457-11457
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Dr. Eddy W. T. Yemeli Dr. Graeme R. Blake Dr. Alexios P. Douvalis Prof. Thomas Bakas Gert O. R. Alberda van Ekenstein Dr. Petra J. van Koningsbruggen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(72):16766-16776
The iron(III) spin-crossover compounds [Fe(Hthsa)(thsa)] ⋅ H2O ( 1 ), [Fe(Hth5Clsa)(th5Clsa)2] ⋅ H2O ( 2 ), and [Fe(Hth5Brsa)(th5Brsa)2] ⋅ H2O ( 3 ) (H2thsa=salicylaldehyde thiosemicarbazone, H2th5Clsa=5-chlorosalicylaldehyde thiosemicarbazone, and H2th5Brsa=5-bromosalicylaldehyde thiosemicarbazone) have been synthesized and their spin-transition properties investigated by magnetic susceptibility, Mössbauer spectroscopy, and differential scanning calorimetry measurements. The three compounds exhibit an abrupt spin transition with a thermal hysteresis effect. The more polarizable the substituent on the salicylaldehyde moiety, the more complete is the transition at room temperature with an increased degree of cooperativity. The molecular structures of 1 and 2 in the high-spin state are revealed. The occurrence of the light-induced excited-spin-state trapping phenomenon appears to be dependent on the substituent incorporated into the 5-position of the salicylaldehyde subunit. Whereas the compounds with an electron-withdrawing group (-Br or -Cl) exhibit light-induced trapped excited high-spin states with great longevity of metastability, the halogen-free compound does not, even though strong intermolecular interactions (such as hydrogen-bonding networks and π stacking) operate in the system. For compound 2 , the surface level of photoconversion is less than 35 %. In contrast, compound 3 displays full photoexcitation. 相似文献
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Jakob Woisetschl?ger Adam D. Wexler Gert Holler Mathias Eisenhut Karl Gatterer Elmar C. Fuchs 《Experiments in fluids》2012,52(1):193-205
When a high-voltage direct-current is applied to two beakers filled with polar liquid dielectrica like water or methanol,
a horizontal bridge forms between the two beakers. By repeating a version of Pellat’s experiment, it is shown that a horizontal
bridge is stable by the action of electrohydrodynamic pressure. Thus, the static and dynamic properties of the phenomenon
called a ‘floating water bridge’ can be explained by the gradient of Maxwell pressure, replenishing the liquid within the
bridge against any drainage mechanism. It is also shown that a number of liquids can form stable and long horizontal bridges.
The stability of such a connection, and the asymmetry in mass flow through such bridges caused by the formation of ion clouds
in the vicinity of the electrodes, is also discussed by two further experiments. 相似文献
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