We have located links that may give you full text access.
Investigations on the photochromic properties of 2,6-bis(5-bromo-2-hydroxybenzylidene)cyclohexanone.
Photochemical & Photobiological Sciences 2017 June 15
The network of chemical reactions of 2,6-bis(5-bromo-2-hydroxybenzylidene)cyclohexanone (BHBC) when subjected to light and different pH values has been investigated. The pH dependent species involved in the chemical network have been identified and characterized by NMR and UV-VIS spectroscopy. Direct pH jumps were carried out by adding a strong acid to equilibrated solutions of trans-chalcone (Ct) forming the flavylium cation which was stable only under extremely acidic conditions (pH < 0.5). The single crystal X-ray study and NMR analysis has confirmed the structure of the new flavylium cation. In the case of a reverse pH jump, the Ct species interconverted instantaneously into deprotonated trans-chalcone (Ct2- ) around pH 12. A new colorless compound 3,11-dibromo-7,8-dihydro-6H-chromeno[3,2-d]xanthene (B-B) isolated from the equilibrated solution of trans-chalcone species in methanol after long periods of time (100 h) under dark conditions has been isolated and fully characterized by NMR and X-ray diffraction. The rate of the reaction increased when the solution of trans-chalcone was exposed to light and the total conversion of Ct into the spiropyran-like compound (B-B) was achieved in about 30 minutes. The B-B form was stable under neutral and basic conditions, while at low pH values it converts into a cationic AH+ form.
Full text links
Related Resources
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app