30906-99-1Relevant academic research and scientific papers
Sensibilisation du photochromisme de spirooxazines par transfert d'energie triplet-triplet
Eloy, D.,Escaffre, P.,Gautron, R.,Jardon, P.
, p. 897 - 914 (2007/10/02)
The present publication describes sensitized photocoloration by triplet-triplet energy transfer of some photochromic spirooxazines.The dominant reaction leading to the colored dye product B in the direct photolysis of the spirooxazine (SPO) in toluene involves the singlet excited state but the results obtained in this work show that both triplet and singlet states are involved in the color-forming reaction.We employed sensitizers of decreasing triplet energy in an attempt to locate the triplet level in the SPO.From the triplet energies of the sensitizers of the SPO color formation it can be concluded that the energy of the spirooxazine triplet state is about 212 kJ.mol-1.The camphorquinone (CQ) sensitizes the formation of B.This compound is particularly suitable for investigation of sensitized photocoloration of spirooxazines since it absorbs in a region of the spectrum where SPO does not absorb (λmax = 471 nm).Then, it is possible to extend the photochromic properties of the SPO to the visible region (λ 500 nm) for industrial applications.The absorption spectra of the colored form were determined for the direct and sensitized photolysis in toluene solutions.
SYNTHESE DE QUELQUES SPIRO ET SPIRO PHOTOCHROMIQUES. APPLICATION DE LA METHODOLOGIE DE LA RECHERCHE EXPERIMENTALE
Pottier, E.,Sergent, M.,Luu, R. Phan Tan,Guglielmetti, R.
, p. 719 - 740 (2007/10/02)
Some spiro I and spiro II substituted by different groups were synthesized in order to evaluate their photochromic properties and to optimize the preparation of spiroheterocyclic systems.In addition, some spiro III were also prepared as reference compounds.Their physical and spectroscopic characteristics (UV, 1H and 13C) were determined.A study using the experimental design methodology allowed to point out the most important factors for improving the reaction yields. KEYWORDS: Photochromism, spirooxazines, spiropyrans, synthesis, 1H NMR, experimental design methodology.
