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Vanadium-substituted polycationic Al-oxo cluster in a porous ionic crystal exhibiting Lewis acidity
Wei Zhou1, Naoki Ogiwara1, Zhewei Weng1
1Department of Basic Science, School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan. cogiwara@g.ecc.u-tokyo.ac.jp.
Abstract:
Herein we present the first example of a vanadium-substituted δ-Keggin Al13-based (Al28V4) porous Ionic crystal (PIC) (Al28V4-PW9V3). Structural and theoretical studies suggested that Al28V4 may exhibit Lewis acidity, which was confirmed by acetalization reaction with Al28V4-PW9V3 as a solid catalyst and investigations with pyridine or 2,6-lutidine as basic probe molecules. A comparative study with the δ-Keggin Al13 monomer based PIC indicated that the vanadium-substitution gave rise to the Lewis acidity.
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