abstract
a-Extended derivatives of the electron donor (D) alpha-dithiophenetetrathiafulvalene (alpha-DT-TTF) were prepared for the first time. The compounds consisting of alpha-DT-TTF covalently linked to N-alkylated phthalimides (Phth) or thieno[3,4-c]pyrrole-4,6-dione (TPD), as the acceptors (A), in a A-D-A arrangements, were synthesized through microwave-assisted Stille cross-coupling reactions. DFT calculations reveal that the alpha-DT-TTF unit is coplanar with the TPD plane while a light twist occurs with the Phth end-unit, causing highly planar conjugated cores which are favorable for stacking and intermolecular charge transport. The A-D-A molecular design leads to redshifted absorption spectra, in comparison with alpha-DT-TTF, and accessible reduction potentials, as indicated by electrochemical studies. Finally, photoconductivity in the UV-visible, up to 550 nm, was measured in crystals of one of the new compounds with the acceptor phthalimide. This work opens the way for the synthesis of new alpha-DT-TTF derivatives which can have applications in the optoelectronics field.
keywords
ELECTRON-TRANSFER; DERIVATIVES; COMPLEXES; POLYMERS; SALTS
subject category
Chemistry; Engineering; Materials Science
authors
Velho, MFG; Paracana, A; Sarra, J; Alcacer, L; Avo, J; Almeida, M; Belo, D; Alves, H; Charas, A
our authors
Helena Alves
Principal ResearcherProjects
Materiais Neutros Solúveis para a Electrónica Molecular (NEUTRABILITY)
Sensores de temperatura, gases e humidade baseados em grafeno para a eletronica têxtil (Graphsense)
acknowledgements
This work was funded by FCT/MCTES (Portugal) through national funds and when applicable co-funded EU funds under the contracts UIDB/EEA/50008/2020, PTDC/QUI-QIN/29834/2017, PTDC/QUI-QFI/32007/2017, and POCI-01-0145-FEDER-032072. J. Avo (SFRH/BPD/120599/2016) acknowledges FCT for a Postdoc grant and A. Paracana (2020.06159.BD) , J. Serra (SFRH/BD/145160/2019) and M.F.G. Velho (PD/BD/135314/2017) also acknowledge FCT for PhD grants.