C?C Bond Formation via Carbon-Centered Radicals Generated from Dicarbonyl(η5-cyclopentadienyl) organoiron Complexes

Irradiation of benzyldicarbonyl(η⁵-cyclopentadienyl)iron complex ( 2 ) leads to hemolytic cleavage of the Fe? C bond. In the presence of activated alkenes, radical addition occurs and both saturated and unsaturated addition products 7–9 are formed. Photolysis of alkyliron complexes 2 , 3 and 20 in the presence of acrylonitrile leads to the same products as the irradiation of the respective acyliron complexes 28–30 . This indicates that, under photolytical conditions, alkyl and acyl complexes are in equilibrium with each other.     

Fundamental groups of commuting elements in Lie groups

We compute the fundamental group of the spaces of ordered commutingn-tuples of elements in the Lie groups SU(2), U(2) and SO(3).For SO(3) the mod-2 cohomology of the components of these spacesis also obtained.     

Selenium-sulfur analogs. Mass spectrometric comparison of substituted selenazoles and thiazoles

The electron impact mass spectra of a series of thiazoles and selenazoles were compared. No major differences in the mass spectral behavior between the sulfur and selenium containing compounds were observed. Isotopic labelling with deuterium permitted deconvolution of ion peaks of identical mass and composition, but arising from different fragmentation pathways.     

Schnellbestimmung niedriger Wassergehalte in Kieselgelen mit einem R?ntgenfluorescenzspektrometer

Ohne Zusammenfassung

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Rapid determination of low water contents in silica gels by means of an X-ray fluorescence spectrometer

     

Evidence for vibrational excitation in H+ + CH4, CD4 collisions by means of a surface-hopping mechanism

The energy-loss spectra for H⁺ scattered at small angles from CH₄ and CD₄ display an unusual bimodal character and extremely large average excitation energies. We propose a potential energy surface-hopping mechanism to account for the novel features of this system.