TY - JOUR
T1 - Fluoride Ion-Encapsulated Germoxane Cages Modified with Organosiloxane Chains as Anionic Components of Ionic Liquids
AU - Hayashi, Taiki
AU - Murase, Nanako
AU - Sato, Naoto
AU - Fujino, Koki
AU - Sugimura, Natsuhiko
AU - Wada, Hiroaki
AU - Kuroda, Kazuyuki
AU - Shimojima, Atsushi
N1 - Funding Information:
We thank Y. Watabe (Material Characterization Central Laboratory, Waseda University) for DSC analysis, Y. Niijima and K. Toyoda (Waseda University) for GPC analysis, Y. Hattori (Waseda University) for MALDI-TOF mass analysis, Y. Miyamoto (Waseda University) for contact angle measurement, and Dr. K. Muramatsu (Shinshu University), Dr. T. Matsuno, Dr. M. Koike, M. Yatomi, T. Hikino, R. Tanaka, T. Harigaya, M. Suzuki, and M. Kikuchi (Waseda University) for fruitful discussions. This work was supported in part by a grant-in-aid for scientific research (B) (grant number 20H02826) and JST SPRING (grant number JPMJSP2128). This work was the result of using research equipments (JEOL JNM ECZ 500, Bruker AVANCE 600 NEO, Bruker Autoflex maX, JEOL JMS T100 CS AccuTOF, RIGAKU ThermoMass, and Perkin Elmer DSC8500: Material Characterization Central Laboratory) shared in the MEXT Project for promoting public utilization of advanced research infrastructure (program for supporting construction of core facilities) (grant number JPMXS0440500021). T.H. is grateful to The Public interest Satomi Scholarship Foundation.
Funding Information:
We thank Y. Watabe (Material Characterization Central Laboratory, Waseda University) (47) for DSC analysis, Y. Niijima and K. Toyoda (Waseda University) for GPC analysis Y. Hattori (Waseda University) for MALDI-TOF mass analysis, Y. Miyamoto (Waseda University) for contact angle measurement, and Dr. K. Muramatsu (Shinshu University), Dr. T. Matsuno, Dr. M. Koike, M. Yatomi, T. Hikino, R. Tanaka, T. Harigaya, M. Suzuki, and M. Kikuchi (Waseda University) for fruitful discussions. This work was supported in part by a grant-in-aid for scientific research (B) (grant number 20H02826) and JST SPRING (grant number JPMJSP2128). This work was the result of using research equipments (JEOL JNM ECZ 500, Bruker AVANCE 600 NEO, Bruker Autoflex maX, JEOL JMS T100 CS AccuTOF, RIGAKU ThermoMass and Perkin Elmer DSC8500: Material Characterization Central Laboratory) shared in the MEXT Project for promoting public utilization of advanced research infrastructure (program for supporting construction of core facilities) (grant number JPMXS0440500021). T.H. is grateful to The Public interest Satomi Scholarship Foundation.
Publisher Copyright:
© 2022 American Chemical Society. All rights reserved.
PY - 2022/6/13
Y1 - 2022/6/13
N2 - Herein, we report the preparation of a new class of inorganic-organic hybrid ionic liquids by modification of a double-four-ring (D4R)-type germoxane (Ge-O-Ge) compound, containing a fluoride ion inside and a tetraethylammonium cation outside, with organosiloxane chains. D4R-type inorganic compounds are attractive as anionic components of ionic liquids because of their ability to encapsulate a fluoride ion inside the cage and allow various functional groups to be linked at the cage corners. The crystalline D4R-type germoxanes with corner Ge-OH groups were successfully converted to clear liquids by modification with dimethylvinylsilyl groups, followed by hydrosilylation with flexible oligosiloxanes (HSi(OSiMe3)nMe3-n, n = 1-3). The resulting products showed liquid behaviors below 0 °C and were stable against thermal decomposition up to ∼200 °C. Additionally, they had high affinities for both hydrophilic and hydrophobic substances, attributable to the organosiloxane chains surrounding the ionic cage. Furthermore, the differences between the D4R-type germoxane and D4R-type siloxane were investigated using density functional theory calculations. The symmetry of the optimized structure and its electrostatic nature indicated that D4R-type germoxane is advantageous for the creation of ionic liquids.
AB - Herein, we report the preparation of a new class of inorganic-organic hybrid ionic liquids by modification of a double-four-ring (D4R)-type germoxane (Ge-O-Ge) compound, containing a fluoride ion inside and a tetraethylammonium cation outside, with organosiloxane chains. D4R-type inorganic compounds are attractive as anionic components of ionic liquids because of their ability to encapsulate a fluoride ion inside the cage and allow various functional groups to be linked at the cage corners. The crystalline D4R-type germoxanes with corner Ge-OH groups were successfully converted to clear liquids by modification with dimethylvinylsilyl groups, followed by hydrosilylation with flexible oligosiloxanes (HSi(OSiMe3)nMe3-n, n = 1-3). The resulting products showed liquid behaviors below 0 °C and were stable against thermal decomposition up to ∼200 °C. Additionally, they had high affinities for both hydrophilic and hydrophobic substances, attributable to the organosiloxane chains surrounding the ionic cage. Furthermore, the differences between the D4R-type germoxane and D4R-type siloxane were investigated using density functional theory calculations. The symmetry of the optimized structure and its electrostatic nature indicated that D4R-type germoxane is advantageous for the creation of ionic liquids.
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U2 - 10.1021/acs.organomet.2c00174
DO - 10.1021/acs.organomet.2c00174
M3 - Article
AN - SCOPUS:85131934008
SN - 0276-7333
VL - 41
SP - 1454
EP - 1463
JO - Organometallics
JF - Organometallics
IS - 11
ER -