Zhang, Yanbing published the artcileNear-Infrared Fluorescent Thienothiadiazole Dyes with Large Stokes Shifts and High Photostability, Formula: C4Br2N2O4S, the publication is Journal of Organic Chemistry (2017), 82(11), 5597-5606, database is CAplus and MEDLINE.
A series of near-IR (NIR) organic emissive materials were synthesized and the photophys. properties analyzed. The donor-acceptor-donor materials were designed with thienopyrazine and thienothiadiazole acceptor groups with thiophene-, furan-, and triphenylamine-based donor groups. The absorption and emission spectra were found to be widely tunable on the basis of the donor and acceptor groups selected. Computational anal. confirms these materials undergo an intramol. charge-transfer event upon photoexcitation. Large Stokes shifts of ∼150 nm were observed and rationalized by computational anal. of geometry changes in the excited state. Fluorescence studies on the dye series reveal maximum peak emission wavelengths near 900 nm and a quantum yield exceeding 16% for 4,6-bis(2-thienyl)thieno[3,4-c][1,2,5]thiadiazole. Addnl., several dyes were found to have reasonable quantum yields within this NIR region (>1%), with emission wavelengths reaching 1000 nm at the emission curve onset. Photostability studies were conducted on these materials in an ambient oxygen environment, revealing excellent stability in the presence of oxygen from all the dyes studied relative to a benchmark cyanine dye (ICG) during photoexcitation with exceptional photostability from the 4,6-bis(5′-dodecyl-[2,2′-bithiophene]-5-yl)thieno[3,4-c][1,2,5]thiadiazole derivative
Journal of Organic 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 C5H10O, Formula: C4Br2N2O4S.
Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary