TY - JOUR
T1 - Kinetic Stabilization of Carbazole Nitroxides by Inclusion in a Macrocage and Their Electron Spin Resonance Characterization
AU - Hashimoto, Hikaru
AU - Inagaki, Yusuke
AU - Momma, Hiroyuki
AU - Kwon, Eunsang
AU - Setaka, Wataru
N1 - Funding Information:
This work was supported by a JSPS Grant-in-Aid for Scientific Research on Innovation Areas “stimuli-responsive chemical species” (JP15H00955), Scientific Research (B) (JP25288042), and Izumi Science and Technology Foundation (2018-J-88). The computations were performed using the Research Center for Computational Science, Okazaki, Japan and Nagoya University ICTS.
Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/9/20
Y1 - 2019/9/20
N2 - Some nitroxides, for example, tetramethylpyridiniumoxide, are known as stable radicals; however, carbazole nitroxide is less stable. The kinetic stabilization of labile radicals by introduction of bulky substituents is usually effective to investigate intrinsic properties of the molecule because of small electronic perturbation induced by the substituents. In this study, macrocage molecules with a carbazole nitroxide connected by covalent bonds were newly designed as kinetically stabilized carbazole nitroxides. The nitroxides were prepared and characterized by electron spin resonance spectroscopy. The caged nitroxides presented long half-lives (∼50 h) by kinetic analysis.
AB - Some nitroxides, for example, tetramethylpyridiniumoxide, are known as stable radicals; however, carbazole nitroxide is less stable. The kinetic stabilization of labile radicals by introduction of bulky substituents is usually effective to investigate intrinsic properties of the molecule because of small electronic perturbation induced by the substituents. In this study, macrocage molecules with a carbazole nitroxide connected by covalent bonds were newly designed as kinetically stabilized carbazole nitroxides. The nitroxides were prepared and characterized by electron spin resonance spectroscopy. The caged nitroxides presented long half-lives (∼50 h) by kinetic analysis.
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U2 - 10.1021/acs.joc.9b01686
DO - 10.1021/acs.joc.9b01686
M3 - Article
C2 - 31442043
AN - SCOPUS:85072392506
SN - 0022-3263
VL - 84
SP - 11783
EP - 11789
JO - Journal of Organic Chemistry
JF - Journal of Organic Chemistry
IS - 18
ER -