- Deuterium and Carbon-13 NMR of the Solid Polymorphism of Benzenehexoyl Hexa-n-hexanoate
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Deuterium and carbon-13 NMR of specifically labeled benzenehexoyl hexa-n-hexanoate in the various solid-state phases are reported.The spectra exhibit dynamic line shapes which change discontinuously at the phase transitions.The results are interpreted in terms of sequential "melting" of the side chains on going from the low-temperature solid phases IV, III, etc., toward the liquid.In phase IV the molecules are very nearly static, except for fast rotation of the methyl groups about their C3 axes.The results in phase III were quantitatively interpreted in terms of a two-site isomerization process ivolving simultaneous rotation by 95 deg about C1-C1 and transition from gtg to g'g't (or equivalently g'tg' to ggt) for the rest of the chain.The specific rate of this reaction at 0 deg C is ca. 1E5 s-1.In phase II additional chain isomerization processes set-in which were, however, not analyzed quantitatively.Further motional modes, involving reorintation of whole chains about their Car-O bonds, appear on going to phase I.In all solid phases the benzene ring remains static.
- Lifshitz, E.,Goldfarb, D.,Vega, S.,Luz, Z.,Zimmermann, H.
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- A McLafferty Rearrangement in an Even-electron System: C3H6 Elimination from the α-Cleavage Product of Tri-n-butylamine
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It is shown by deuterium labelling, linked-scan measurements and collision activation that the .>+ (α-cleavage) ion in the electron impact ionization spectrum of tributylamine loses C3H6 with transfer of one hydrogen specifically from the γ-position.The experimental data point towards a mechanism which involves the intermediate formation of a distonic diradical ion from an excited α-cleavage ion which the eliminates the neutral alkene.
- Budzikiewicz, Herbert,Bold, Peter
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- DEUTERATED LORCASERIN
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This invention relates to novel compounds that are 3-benzazepine derivatives and pharmaceutically acceptable salts thereof. More specifically, this invention relates to novel 3-benzazepine derivatives that are derivatives of lorcaserin. This invention als
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(2009/05/28)
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