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Author Spotlight: Accelerating Discovery in Microporous Material Chemistry

Author Spotlight: Accelerating Discovery in Microporous Material Chemistry

Published on: October 6, 2023

Isomeric effects on the acidity of Al₁₃ Keggin clusters in porous ionic crystals

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. csayaka@g.ecc.u-tokyo.ac.jp.

Chemical Communications (Cambridge, England)

|August 6, 2021

Abstract:

We demonstrate a facile synthesis method of a porous ionic crystal (PIC) composed of the little-known δ-Keggin-type cationic polyoxoaluminum cluster ([δ-Al₁₃O₄(OH)₂₄(H₂O)₁₂]⁷⁺, δ-Al₁₃) with an oppositely-charged polyoxometalate, which enabled us to investigate the activity as a solid acid. The δ-Al₁₃ based PIC exhibited much higher activity in pinacol rearrangement, a typical acid-catalyzed reaction, than the PIC based on the well-known and thermodynamically stable rotational isomer (ε-Al₁₃). This work is a rare example of rotational isomers of polyoxoaluminum clusters exhibiting remarkably different catalytic activities.

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