Photochromic Radical Complexes That Show Heterolytic Bond Dissociation
- 2 May 2020
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 142 (22), 10132-10142
- https://doi.org/10.1021/jacs.0c02739
Abstract
Photochromic materials have been widely used in various research fields because of their variety of photoswitching properties based on various molecular frameworks and bond breaking processes such as homolysis and heterolysis. However, while a number of photochromic molecular frameworks have been reported so far, there are few reports on photochromic molecular frameworks that show both homolysis and heterolysis depending on the substituents with high durability. The biradicals and zwitterions generated by homolysis and heterolysis have different physical and chemical properties, and different potential applications. Therefore, the rational photochromic molecular design to control the bond dissociation in the excited state on demand expands the versatility for photoswitch materials beyond the conventional photochromic molecular frameworks. In this study, we synthesized novel photochromic molecules based on the framework of a radical dissociation-type photochromic molecule: phenoxyl-imidazolyl radical complex (PIC). While the conventional PIC shows the photoinduced homolysis, the substitution of a strong electron-donating moiety to the phenoxyl moiety enables to switch the bond dissociation process from homolysis to heterolysis. This study gives a strategy for controlling the bond dissociation process of the excited state of photochromic systems, and the strategy enables to develop further novel radical and zwitterionic photoswitches.Funding Information
- Japan Society for the Promotion of Science (JP18H05263, JP18K14194)
This publication has 46 references indexed in Scilit:
- Photon-Working SwitchesPublished by Springer Science and Business Media LLC ,2017
- Photochromism of Diarylethene Molecules and Crystals: Memories, Switches, and ActuatorsChemical Reviews, 2014
- Enhancing the Versatility and Functionality of Fast Photochromic Bridged Imidazole Dimers by Flipping Imidazole RingsJournal of the American Chemical Society, 2014
- Ultrafast Dynamics of Photochromic SystemsChemical Reviews, 2000
- Photochromic Color Change of the Dimer of Triphenylimidazolyl at Low TemperaturesBulletin of the Chemical Society of Japan, 1969
- Photodissociation of Nitroso DimersNature, 1967
- C-nitroso compounds. Part I. The formation of nitroxides by photolysis of nitroso compounds as studied by electron spin resonance.Tetrahedron Letters, 1966
- The Mechanism of the Photochromism and Thermochromism of 2,2′, 4,4′, 5,5′-Hexaphenyl-1,1′-biimidazolyl in a Solid StateBulletin of the Chemical Society of Japan, 1965
- THE PHOTOTROPY OF TETRACHLOROKETODIHYDRONAPHTHALENE AS A REVERSIBLE PHOTOCHEMICAL REACTION1The Journal of Physical Chemistry, 1962
- Preparation of a New Phototropic SubstanceBulletin of the Chemical Society of Japan, 1960