A research team led by Prof. Liu Zhongmin and Prof. Wei Yingxu fromDalian Institute of Chemical Physicsof the Chinese Academy of Sciences (CAS) reportedanalternativeroute—cyclopentadienes-based cycle of methanol to olefins catalyzed by H-RUB-50.The results were published inJournal of Energy Chemistry(https://doi.org/10.1016/j.jechem.2019.09.022).
In thiswork, trimethylcyclopentenyl cation (triMCP+) and its deprotonated counterpart (trimethylcyclopentadiene,triMCP) were directly captured on H-RUB-50 catalyst with small cavity by the aid ofin situ13C MAS NMR spectroscopy, and their higher catalytic reactivity were clarified by12C/13C-CH3OH isotopic switch experiment. An alternative route—cyclopentadienes-based cycle was evaluatedin methanol conversion catalyzed by H-RUB-50 with small cavity, in which ethene was produced with the participation of triMCP+as critical intermediate. Then the cyclopentadienes-based cycle was predicted to be energetically favourable for ethene formation by density functional theory(DFT) calculations.
Furthermore, the steric constraint imposed by small cavity of H-RUB-50 associated with the host-guest interaction determines the formation of the small-sized intermediates and their reaction routes. This work highlights the role of methylcyclopentenyl cation (MCP+) and the importance of host-guest interaction induced by the cavity structure in the formation of intermediates and reaction pathway.
This work was supported by the National Natural Science Foundation of China and the Key Research Program ofFrontier Sciences, Chinese Academy of Sciences.（Text by Zhang Wenna）
Methylcyclopentenyl Cation Mediated Reaction Route in Methanol-to-Olefins Reaction over H-RUB-50 with Small Cavity. Wenna Zhang, Shutao Xu , Yuchun Zhi , Yingxu Wei *, Zhongmin Liu *, Journal of Energy Chemistry, 45:25-30, 2020.
