Large polarization of push–pull 'Cruciforms' via coordination with lanthanide ions

Autor:	Mercedes M. A. Mazza, Dario Pasini, Daniele Dondi, Sara Benedini, Andrea Nitti, Yeting Zheng, Françisco M. Raymo
Rok vydání:	2022
Předmět:	Lanthanide Chemistry Ligand Supramolecular chemistry General Chemistry Conjugated system Chromophore Acceptor Catalysis Metal Crystallography Intramolecular force visual_art Materials Chemistry visual_art.visual_art_medium
Zdroj:	New Journal of Chemistry. 46:221-227
ISSN:	1369-9261 1144-0546
DOI:	10.1039/d1nj04358g
Popis:	We report on two different series of conjugated push-pull compounds bearing dimethylamino donor and 1,3-dicarbonyl acceptor functionalities with a “bent” or“cruciform” shape, exhibit striking differences in their supramolecular recognition of lanthanide cations. Both series of compounds are effective to coordinate lanthanide cations (Sc3+ and Eu3+) in MeCN, CHCl3 or MeOH solutions to the 1,3-dicarbonyl acceptor end. The stoichiometry of the complexes are largely dependent on the nature of the lanthanide cation, with Sc3+ forming preferentially 1:3 metal:ligand complexes, and Eu3+ forming 1:1 metal:ligand complexes. The coordination of the lanthanide cation results in an overall supramolecular polarization of the system and the redshifting of the intramolecular charge transfer band. The polarization of the “cruciform” systems is greatly enhanced with respect to the “bent” chromophores, reaching outstanding values for the red shift (238 nm, corresponding to an energy difference of 1.23 eV) with high binding constants (Log Ka >5.5).
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::81dbf3b5d1956be2827ce64b127d1b64 https://doi.org/10.1039/d1nj04358g Zobrazit plný text záznamu