Trialkylaminate der Dialkyl-aluminiumhydride reagieren bereits bei 20-40 O C in uberschussigem Trialkylamin lebhaft mit I-Alkinen zu den Aminaten der Dialkyl-aluminium-al-Entsprechend lassen sich beini Acetylen beidc Wasserstoffatome durch die RrAl-Gruppe ersetzen. Man e r h d t ein stabiles Monoaminat mit doppeltem Molekulargewicht. Aluminiumtrialkyl-trialkylaminate liefern bei 1O0-I2OgC ebenfalls (I); R ' H wird abgespalten. Die bekannte Addition der AI-H-und At-C-Bindung a n die Dreifachbindung [ I ] crfolgt in Gegenwart der Amine nicht. Dagegen reagieren die Atherate der Dialkyl-aluminiumhydride rnit 1-Alkinen erst oberhalb IOO"C, wobei die AIH-Gruppe infolge Dissoziation von RzAIH.OR2 hauptsichlich an die Dreifachbindung addiert wird. Die Atherate der Aluminiumtrialkyle zeigen unter den gleichen Bedingungen keine Reaktion. Aus ihren Aminaten lassen sich die freien Dialkyl-aluminiumalkinyle durch Umsatz mit Aluminiumtrialkylcn gewinnen, z. B. Propinyl-und Butinyl-Derivate nach (a).
It was discovered that the noble gases Ar, Kr and Xe can be trapped firmly in type A zeolites as well as in mordenites and chabazites when the molecular sieves are hydrothermally vitrified at temperatures between 340 and 650°C in the presence of pressurized gas. The occurrence of trapping in an amorphous nonzeolitic species was demonstrated by X‐ray diffraction, neutron scattering and electron scattering. The change in structure of loaded zeolites is also manifested by a substantial loss in sorption capacity for water as well as an almost complete disappearance of the specific surface area. – The gas release rates at temperatures below 550°C were found to be extremely low. The activation energies for the diffusion of Kr through amorphous Ca and Mg exchanged 5 A zeolite were determined to be 209 ± 15 and 187 ± 16 kJ/mol respectively. The estimated diffusion coefficients are exceedingly small. The trapped gas is neither liberated by hot water nor by liq. Rb at 150°C.
The electron impact induced fragmentation of 1,3-diphenyl-2-pyrazoline was studied by nitrogen-15, carbon-13 and deuterium labelling, substitution in the para position of one of the phenyl rings by fluoro and methoxy groups, and ion kinetic energy spectroscopy, as well as accurate mass measurements. In the fragmentation pathway observed all the ions in the mass spectrum of 1,3-diphenyl-2-pyrazoline (except mle103) originate from the molecular ion, which in all compounds is the base peak. The formation of prominent fragment ions is discussed.
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