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Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments
Published on: May 11, 2017
A Stable Neutral Radical in the Coordination Sphere of Aluminum
Bin Li1,2, Subrata Kundu1, A Claudia Stückl1
1Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, 37077, Göttingen, Germany.
Abstract:
The neutral radical (Me2 -cAAC)2 AlCl2 (2) is stabilized by cyclic (alkyl)(amino)carbenes (cAACs). Complex 2 was synthesized by reduction of the Me2 -cAAC:→AlCl3 (1) adduct with KC8 in the presence of another equivalent of Me2 -cAAC. The crystal structure of 2 shows that the Al-C bond lengths of the two carbenes bound to the Al center are considerably different, which is likely the result of intermolecular interactions. Quantum-chemical calculations from the gas phase give an equilibrium structure with identical Al-C bond lengths. Compound 2 exhibits monoradical character, which was confirmed by EPR measurements. A bonding analysis indicates that the unpaired electron resides mainly at the carbene carbon atoms. Compound 2 is an example for an unusual neutral Al radical.
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