N,N′-Disubstituted Indigos as Readily Available Red-Light Photoswitches with Tunable Thermal Half-Lives
Some rare indigo derivatives have been known for a long time to be photochromic upon irradiation with red light, which should be advantageous for many applications. However, the absence of strategies to tune their thermal half-lives by modular molecular design as well as the lack of proper synthetic methods to prepare a variety of such molecules from the parent indigo dye have so far precluded their use. In this work, several synthetic protocols for N-functionalization have been developed, and a variety of N-alkyl and N-aryl indigo derivatives have been prepared. By installation of electron-withdrawing substituents on the N-aryl moieties, the thermal stability of the Z-isomers could be enha…
Searching for new borondifluoride β -diketonate complexes with enhanced absorption/emission properties using ab initio tools
International audience; The rational design of fluorophores with enhanced absorption/emission properties increasingly relies on theoretical chemistry, as new ab initio methods suited for electronically excited-states reduce the gap between calculated and experimental results. In this framework, Time-Dependent Density Functional Theory (TD-DFT) emerges as an attractive option as it often provides accurate results at a moderate computational cost. Here, we perform a TD-DFT-SOS-CIS(D) study of a panel of 18 borondifluoride β-diketonate complexes that can be classified as: curcuminoids, hemicurcuminoids, their ethynylene analogues, and 2′-hydroxy-chalcones. First, we reproduce the experimental …
Coumarin-Phosphine-Based Smart Probes for Tracking Biologically Relevant Metal Complexes: From Theoretical to Biological Investigations
International audience; Ten metal-based complexes and associated ligands have been synthesized and characterized. One of the metal ligands is a coumarin-phosphine derivative, which displays tunable fluorescence properties. The fluorescence is quenched in the case of the free ligand and ruthenium and osmium complexes, whereas it is strong for the gold complexes and phosphonium derivatives. These trends were rationalized by theoretical calculations, which revealed non-radiative channels involving a dark state for the free ligands that is lower in energy than the emissive state and is responsible for the quenching of fluorescence. For the Ru-II and Os-II complexes, other non-radiative channels…
Rationalisation of the Optical Signatures of nor-Dihydroxanthene-Hemicyanine Fused Near-Infrared Fluorophores By First Principle Tools
Using a computational approach combining the Time-Dependent Density Functional Theory (TD-DFT) and the second-order Coupled Cluster (CC2) approaches, we investigate the spectral properties of a large panel of nor-dihydroxanthene (DHX)-hemicyanine fused dyes. First we compare the theoretical and experimental 0-0 energies for a set of 14 known synthetic compounds and show that a remarkable agreement between theory and experiment is obtained when a suitable environmental model is selected. In addition, we obtain vibrationally-resolved spectra for several compounds and theory also accurately reproduces the experimental band shapes. We show that the electronic transitions in nor-DHX-based fluoro…
CCDC 1420553: Experimental Crystal Structure Determination
Related Article: Lucile Dondaine, Daniel Escudero, Moussa Ali, Philippe Richard, Franck Denat, Ali Bettaieb, Pierre Le Gendre, Catherine Paul, Denis Jacquemin, Christine Goze and Ewen Bodio|2016|Eur.J.Inorg.Chem.||545|doi:10.1002/ejic.201501304
CCDC 1420552: Experimental Crystal Structure Determination
Related Article: Lucile Dondaine, Daniel Escudero, Moussa Ali, Philippe Richard, Franck Denat, Ali Bettaieb, Pierre Le Gendre, Catherine Paul, Denis Jacquemin, Christine Goze and Ewen Bodio|2016|Eur.J.Inorg.Chem.||545|doi:10.1002/ejic.201501304
CCDC 1565864: Experimental Crystal Structure Determination
Related Article: Chung-Yang Huang, Aurelio Bonasera, Lachezar Hristov, Yves Garmshausen, Bernd M. Schmidt, Denis Jacquemin, Stefan Hecht|2017|J.Am.Chem.Soc.|139|15205|doi:10.1021/jacs.7b08726