Photochromic Properties of Perhydro- and Perfluorodithienylcyclopentene Molecular Switches
作者:Jaap J. D. de Jong、Linda N. Lucas、Ralph Hania、Audrius Pugzlys、Richard M. Kellogg、Ben L. Feringa、Koos Duppen、Jan H. van Esch
DOI:10.1002/ejoc.200200719
日期:2003.5
Various substituted phenylthienyl perhydro- and perfluorocyclopentenes have been synthesized in order to compare their spectroscopic and photochromicproperties. The difference in the electron densities of the central cyclopentene moieties in the perhydrocyclopentene and perfluorocyclopentene molecularswitches has only a small effect on the absorption maxima of the electronic spectra, but causes some
Synthesis of Symmetrical and Nonsymmetrical Bisthienylcyclopentenes
作者:György Szalóki、Jean-Luc Pozzo
DOI:10.1002/chem.201301645
日期:2013.8.19
enabled them to find widespread applications in the field of photochromism. Nowadays, bisthienylcyclopentenes (BTCs) present the most popular subfamily of these compounds, which are widely used as P‐type chromophores. This minireview summarises the main strategies for the synthesis of symmetrical and nonsymmetrical BTCs. In addition, attention is drawn to desymmetrisations achieved by monosubstitutions
Raman scattering and FT-IR spectroscopic studies on dithienylethene switches—towards non-destructive optical readout
作者:Jaap J. D. de Jong、Wesley R. Browne、Martin Walko、Linda N. Lucas、Lindsay J. Barrett、John J. McGarvey、Jan H. van Esch、Ben L. Feringa
DOI:10.1039/b603914f
日期:——
The non-destructive readout of photochromic memory materials based on the dithienylethene unit both by IR spectroscopy and Raman scattering is explored. A representative series of C5-substituted thienyl hexahydro- and hexafluoro-cyclopentene based photochromes was investigated to explore the effect and potential usefulness of substitution for the development of multicomponent memory materials. The effect of the deposition method on the photochemistry of solid materials containing photochromic dithienylcyclopentene switches was also explored. Photoconversion in the solid state to the closed form was found to be low when starting from the open form, but, in contrast, ring opening to the open state from the closed form was found to be complete. The effect was found to be due to inner filter rather than conformational phenomena. Characteristic vibrational bands for the central dithienyl core are assigned and a comparison made of the vibrational spectroscopic properties of the perhydro- and perfluoro switches. The data enable the determination of the photoconversion achievable in the solid state as well as some assessment of the influence of the deposition method on the photoconversion. The potential of Raman spectroscopy as a method of achieving non-destructive optical readout is demonstrated through the large differences in absolute Raman scattering intensity between the open and closed states, when monitored at wavelengths which do not result in photochemical ring opening.
A series of diarylethenes with substituents of different size and chemical nature was synthesised showing that beside some intermolecular interactions involving the central diarylethene core, lateral groups clearly play a key role in the crystal packing arrangements. These structural features were further analyzed in relation to the thermal data obtained by differential scanning calorimetry (DSC) and