Synthesis, optical and electrochemical properties of a series of push-pull dyes based on the 2-(3-cyano-4,5,5-trimethylfuran-2(5H)-ylidene)malononitrile (TCF) acceptor

Abstract

A series of chromophores was designed and synthesized using 2-(3-cyano-4,5,5-trimethylfuran-2 (5H) -ylidene) malononitrile (TCF) as the electron acceptor and differing from each other by the use of thirteen different electron donors. The different dyes were characterized for their optical and electrochemical properties and theoretical calculations were also carried out to support the experimental results. By changing the electron donor in the thirteen dyes, chromophores absorbing between 430 nm and 700 nm could be synthesized. Solvatochromism of the different dyes was analyzed in 23 solvents of different polarity and a positive solvatochromism was determined for all chromophores using the semi-empirical solvent polarity scales based on the Kamlet-Taft parameters (π *) or the Catalan parameters (SdP and SPP).

High-performance sunlight induced polymerization using novel push-pull dyes with high light absorption properties

“…The Ar • and EDB • (-H) radicals formed from Iod and EDB in presence of dye during the irradiation with the LED could be detected in the different solutions, as a confirmation of the proposed chemical mechanism mentioned above 45. The solutions constituted by a mixture of the selected dyes (dyes 1,3,6) and the Iodonium salt (or EDB) in tert-butylbenzene at weight concentration ratio ([dye]=0.2 mg/mL; [Iod]= 2 mg/mL; [EDB]=2 mg/mL) under protection gas, N2, then the spin trap agent, PBN (2 mg/mL), was also dissolved into the solution. The experimental results and ESR spectra of dyes with Iod (or EDB) both before and after irradiation at 405 nm are presented in Figure…”

“…Push-pull dyes are also characterized by an intense absorption band located in the visible range and this absorption band typically corresponds to the intramolecular charge transfer (ICT) band, whose position can be finely tune by chemical engineering. [1][2][3][4][5] Benefiting from their high molar extinction coefficients and excellent photoinitiation abilities in photopolymerization, push-pull dyes based on D-π-A structures (with D and A which stands for donor and acceptor respectively) have been proposed as visible light sensitive photoinitiators since 2013. [6][7][8][9][10] Considering that push-pull dyes can easily exhibit high molar extinction coefficients, compounds of this family were thus candidates of choice for practical applications in Organic Electronics including organic photovoltaics (OPVs), 11,12 organic light-emitting diodes (OLEDs), 13 organic-field effects transistors (OFETs), 14 nonlinear optics (NLO) [15][16][17][18][19] to waste-water treatment.…”

Novel Push–Pull Dyes Derived from 1H-cyclopenta[b]naphthalene-1,3(2H)-dione as Versatile Photoinitiators for Photopolymerization and Their Related Applications: 3D Printing and Fabrication of Photocomposites

“…Among them, organic electronics, including organic photovoltaics (OPVs) [6,7], organic light-emitting diodes (OLEDs) [8], organic-field effects transistors (OFETs) [9] but also nonlinear optics (NLO) [10][11][12][13][14][15][16], water waste treatment [17] or the design of organic probes for diagnostics or bioimaging [18,19], can be cited as a popular research field. By separating the electron-donating group from the electron-accepting group, a strong electronic delocalization can be induced, furnishing molecules with high molar extinction coefficients and displaying a strong absorption band in the visible range corresponding to the intramolecular charge transfer (ICT) band [20][21][22][23][24]. By finely tuning both the electron-donating and electron-accepting abilities of the two partners as well as on the length of the spacer, the molar extinction coefficients but also the position of the ICT band can be carefully controlled [2].…”

Organic dye‐based photoinitiating systems for visible‐light‐induced photopolymerization

“…By improving the electronic delocalization, a significant increase of the molar extinction coefficients can also be achieved. [147][148][149][150][151][152][153][154][155][156][157][158] Thus, push-pull dyes have been widely used as novel PIs due to their interesting features, that were also valorized in applications ranging from Organic Electronics, for example, organic photovoltaics, 159,160 organic light-emitting diodes, 161 organic-field effects transistors 162 to nonlinear optics [163][164][165][166][167][168][169] and waste-water treatment. 170 Over the years, numerous push-pull dyes have been proposed as PIs, as detailed below.…”