Study on novel photochromic systems based on chromophores with six-membered ring as central ethene bridge
type: Dataset
description: A series of photochromic bisthienylethenes (BTE) chromophores with different central ethene bridges were synthesized. Up to date, the rational design of BTE have been mainly carried out on the side aryl groups. In our work, the influence of the aromaticity of the central ethene bridge on the photochromic properties was studied. Moreover, unlike in the literature where most of BTE have a five-membered ring bridge, six-membered ring bridges were used. In Chapter 1, examples of photochromes are given, along with the main definitions. Chapter 2 deals with BTTE, a BTE with a benzobisthiadiazole bridge and with excellent photochromic properties. c-BTTE, the closed isomer, exhibits excellent thermal stability in various solvents and in the solid state. Its fluorescence can be modulated by solvato- and photochromism. It eliminates the usual bias of thermal back reaction, typical of BTE with a six-membered ring ethene bridge. Chapter 3 is devoted to compounds with bridges having different aromaticities (BTE-NA, BTA and BTTA). Their fluorescence can be modulated by solvato- and photochromism. The relation between aromaticity and thermal stability was established: the low aromaticity of the central ethene bridge with benzobisthiadiazole unit leads to a thermal irreversibility for BTTA, and the small energy barrier between the parallel and anti-parallel conformers and the great difference in absorption between BTTA and c-BTTA allow the full conversion from BTTA to c-BTTA. Molecules with a benzothiadiazole bridge, designed for complexation and for switchable nonlinear optical properties were prepared (Chapters 4 and 5). However, the targeted properties were not evidenced up to now.
identifier: NNT: 2012DENS0023
issued: 2026-05-10T06:55:38.344042
language: en
modified: 2026-05-10T06:55:38.344046
contact point: Organization
  fn: CCSD
keyword: aromaticite
keyword: aromaticity
keyword: benzobisthiadiazole
keyword: benzothiadiazole
keyword: bisthienylethene
keyword: chimothechemical-sciencesother
keyword: chromophore
keyword: infoeu-reposemanticsdoctoralthesis
keyword: photochromism
keyword: photochromisme
keyword: theses
landing page: https://theses.hal.science/tel-00846636

Study on novel photochromic systems based on chromophores with six-membered ring as central ethene bridge
type: Distribution
format: HTML
issued: 2026-05-10T06:55:38.354561
modified: 2026-05-10T06:55:38.330261
access URL: https://theses.hal.science/tel-00846636

test_moissonnage_selune
type: Agent