Steinberger, Simon published the artcileSynthesis and characterizations of red/near-IR absorbing A-D-A-D-A-type oligothiophenes containing thienothiadiazole and thienopyrazine central units, Synthetic Route of 52431-30-8, the publication is Journal of Materials Chemistry (2012), 22(6), 2701-2712, database is CAplus.
A series of π-conjugated A-D-A-D-A-type oligothiophenes comprising heterocyclic thieno[3,4-c][1,2,5]thiadiazole or thieno[3,4-b]pyrazine as the core and dicyanovinyl or trifluoroacetyl as terminal acceptor groups have been developed as red/near-IR absorbers. The resulting oligomers were characterized by UV-visible spectroscopy, cyclic voltammetry and thermal anal. The low energy absorption band of these oligomers was located at 620-707 nm in solution and at 695-830 nm in thin films. Theor. studies reveal that the insertion of the bicyclic nonclassical thiophenes to the conjugated backbone imposed partial quinoidal character to the resulting oligomers and thus reduced the band gap. HOMO-LUMO energies of the oligothiophenes derived from electrochem. measurements were found to be suitable for the use as donor material in combination with fullerene-C60 as acceptor in planar heterojunction solar cells prepared by vacuum deposition. Such devices incorporating these low band gap oligomers exhibited high fill factor values up to 0.60, and power conversion efficiencies of up to 1.3% under air-mass 1.5G illumination. External quantum efficiency spectra clearly showed the contribution of the low energy absorption to the overall photocurrent.
Journal of Materials Chemistry published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C7H5Br2F, Synthetic Route of 52431-30-8.
Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary