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Single-Wavelength Visible-Light-Induced Reversible Isomerization of Stiff-Stilbene under Dynamic Covalent Control
Indigo M Bekaert1, Maxime A Siegler2, Sander J Wezenberg1
1Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands.
Abstract:
Formylation of stiff-stilbene enables isomerization by visible instead of UV light, as is monitored by UV-vis and 1H NMR spectroscopy. Further, it allows dynamic covalent imine formation, which gives rise to slightly blue-shifted absorbance. As a result, the irradiation wavelength that is used to promote E → Z isomerization for the formylated species, causes the opposite Z → E isomerization for the imine derivative. This feature can be used to produce either isomer with the same light source under control of imine formation and hydrolysis. Single crystal X-ray analysis and TD-DFT calculations provide structural and electronic insight.
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