A Basic Germanodecatungstate with a −7 Charge: Efficient Chemoselective Acylation of Primary Alcohols†
Kosei Sugahara
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/
Search for more papers by this authorNaoto Satake
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/
Search for more papers by this authorDr. Keigo Kamata
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/
Search for more papers by this authorDr. Takahito Nakajima
RIKEN Advanced Institute for Computational Science, Computational Molecular Science Research Team, 7-1-26 Minatojima-minami-machi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan)
Search for more papers by this authorCorresponding Author
Prof. Dr. Noritaka Mizuno
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/Search for more papers by this authorKosei Sugahara
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/
Search for more papers by this authorNaoto Satake
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/
Search for more papers by this authorDr. Keigo Kamata
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/
Search for more papers by this authorDr. Takahito Nakajima
RIKEN Advanced Institute for Computational Science, Computational Molecular Science Research Team, 7-1-26 Minatojima-minami-machi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan)
Search for more papers by this authorCorresponding Author
Prof. Dr. Noritaka Mizuno
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan) http://park.itc.u-tokyo.ac.jp/mizuno/Search for more papers by this authorThis work was supported in part by the Japan Society for the Promotion of Science (JSPS) through its “Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST Program)” and a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Science, Sports, and Technology of Japan.
Graphical Abstract
Charged up: The title germanodecatungstate [γ-HGeW10O36]7− was synthesized under non-aqueous conditions. The activities of germanodecatungstates for base-catalyzed reactions dramatically increased with an increase in the number of negative charges from −6 to −7. In the presence of [γ-HGeW10O36]7−, various combinations of acylating agents and primary alcohols chemoselectively gave the desired acylated products in high yields.
Abstract
The synthesis of highly negatively charged polyoxometalates with electrically and structurally controlled uniform basic sites can lead to the unique base catalysis. In this work, a γ-Keggin germanodecatungstate, [γ-HGeW10O36]7− (A), having a −7 charge was, for the first time, successfully synthesized by the reaction of [γ-H2GeW10O36]6− with one equivalent of [(n-C4H9)4N]OH under non-aqueous conditions. The activities of germanodecatungstates for base-catalyzed reactions dramatically increased with increase in the number negative charges from −6 to −7. In the presence of A, various combinations of acylating agents and primary alcohols including those with acid-sensitive functional groups chemoselectively gave the desired acylated products in high yields even under the stoichiometric conditions.
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