Proaromatic pyranylidene chalcogen analogues and cyclopenta[c]thiophen-4,6-dione as electron donors and acceptor in efficient charge-transfer chromophores

P. Solanke , S. Achelle (1) , N. Cabon (1) , O. Pytela , A. Barsella (2) , B. Caro (1) , F. Robin-Le Guen (1) , J. Podlesný , M. Klikar , F. Bureš

1 ISCR - Institut des Sciences Chimiques de Rennes
2 IPCMS - Institut de Physique et Chimie des Matériaux de Strasbourg

Fifteen new push-pull chromophores based on a proaromatic pyranylidene donor and its chalcogen analogues and various electron acceptor moieties were synthesized in a straightforward manner. These model molecules were designed and prepared to investigate the concept of proaromaticity as a tool to tune the fundamental properties of push-pull systems. All target chromophores with systematically varied structure were further investigated by electrochemistry, absorption spectra, and EFISH experiment in conjunction with DFT calculations. Employing structural variations such as chalcogen/acceptor replacement, extension of the π-system, and the position of substitution along the pyran ring, the HOMO-LUMO gap can be tuned within the range of 2.18 to 1.41 eV. A new and powerful electron withdrawing moiety, combining features of polarizable thiophene and successful indane-1,3-dione acceptor, cyclopenta[c]thiophen-4,6-dione (ThDione) has also been developed. © 2016 Elsevier Ltd

Mots clés: Charge transfer; Chalcogenopyranylidene; Electron acceptor moieties; Electronwithdrawing; Fundamental properties; Polymethines; Push pull; Push-pull chromophores; Structural variations; Chromophores

Domaines: Chimie

P. Solanke, S. Achelle, N. Cabon, O. Pytela, A. Barsella, et al.. Proaromatic pyranylidene chalcogen analogues and cyclopenta[c]thiophen-4,6-dione as electron donors and acceptor in efficient charge-transfer chromophores. Dyes and Pigments, 2016, 134, pp.129--138. ⟨10.1016/j.dyepig.2016.07.008⟩. ⟨hal-01367232⟩