Kanakubo, Masashi published the artcileRoom-Temperature Phosphorescence of Thiophene Boronate Ester-Cross Linked Polyvinyl Alcohol; A Triplet-to-Singlet FRET-Induced Multi-Color Afterglow Luminescence with Sulforhodamine B, Computed Properties of 239075-02-6, the publication is Bulletin of the Chemical Society of Japan (2021), 94(4), 1204-1209, database is CAplus.
A thiophene-derived boronate ester-crosslinked polyvinyl alc., 1-PVA, has been prepared, which was found to exhibit room-temperature phosphorescence (RTP) at 475 nm upon UV irradiation (λem = 254 nm). The quantum yield (Fp) was determined to be 6.3% with a phosphorescence lifetime of 256 ms, the cyanish afterglow being visually detected after switching the UV lamp off. The emission properties were rationalized by El-Sayed’s rule, where introduction of a sulfur atom brings about n → π* transition in the T2 state to promote an ISC channel. Given that the phosphorescence spectrum at 77 K was consistent with that in the PVA film, the rigid environment of PVA-based matrix may stabilize the triplet state. In addition, the delayed emissive color was tuned by doping various amounts of sulforhodamine B (SRhoB) in the film; a triplet-to-singlet Forster-type resonance energy transfer process occurred from crosslinked thiophene boronate to SRhoB acceptor which modified the emission to a white-light afterglow. Given water-sensitivity of the resultant film, high-contrast water writing on the film was achieved, which would be profitable for a low-cost security film.
Bulletin of the Chemical Society of Japan published new progress about 239075-02-6. 239075-02-6 belongs to alcohols-buliding-blocks, auxiliary class Thiophene,Boronic acid and ester,Boronate Esters, name is 5,5′-Bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,2′-bithiophene, and the molecular formula is C20H28B2O4S2, Computed Properties of 239075-02-6.
Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts