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Concerted Hydrosilylation Catalysis by Silica-Immobilized Cyclic Carbonates and Surface Silanols 40964804 Hasegawa, Shingo Department of Chemistry and Life Science, Yokohama National University Nakamura, Keisuke Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology Soga, Kosuke Department of Chemistry and Life Science, Yokohama National University Usui, Kei Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology Manaka, Yuichi Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology Renewable Energy Research Center, National Institute of Advanced Industrial Science and Technology (AIST) 90444067 Motokura, Ken Department of Chemistry and Life Science, Yokohama National University Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology open access Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International concerted catalysis, surface immobilization, heterogeneous organocatalyst, cyclic carbonate, hydrosilylation Developing a method for creating a novel catalysis of organic molecules is essential because of the growing interest in organocatalysis. In this study, we found that cyclic carbonates immobilized on a nonporous or mesoporous silica support showed catalytic activity for hydrosilylation, which was not observed for the free cyclic carbonates, silica supports, or their physical mixture. Analysis of the effects of linker lengths and pore sizes on the catalytic activity and carbonate C═O stretching frequency revealed that the proximity of carbonates and surface silanols was crucial for synergistic hydrosilylation catalysis. A carbonate and silanol concertedly activated the silane and aldehyde for efficient hydride transfer. Density functional theory calculations on a model reaction system demonstrated that both the carbonate and silanol contributed to the stabilization of the transition state of hydride transfer, which resulted in a reasonable barrier height of 16.8 kcal mol–1. Furthermore, SiO2/carbonate(C4) enabled the hydrosilylation of an aldehyde with an amino group without catalyst poisoning, owing to the weak acidity of surface silanols, in sharp contrast to previously developed acid catalysts. This study demonstrates that immobilization on a solid support can convert inactive organic molecules into active and heterogeneous organocatalysts. American Chemical Society (ACS) 2023-09-15 eng journal article VoR http://hdl.handle.net/10131/0002000040 https://ynu.repo.nii.ac.jp/records/2000040 https://doi.org/10.1021/jacsau.3c00306 26913704 JACS Au 3 10 6 2692 2697 https://ynu.repo.nii.ac.jp/record/2000040/files/jacsau.3c00306.pdf application/pdf 2.5 MB 2023-09-25 2023-09-15