Sun, Jifu; Li, Weixu; Hou, Yuqi; Zhang, Xue; Gao, Zhongzheng; Wang, Bo; Zhao, Jianzhang published an article in 2021. The article was titled 《a-PET and Weakened Triplet-Triplet Annihilation Self-Quenching Effects in Benzo-21-Crown-7-Functionalized Diiodo-BODIPY》, and you may find the article in ACS Omega.Safety of 1-Iodopyrrolidine-2,5-dione The information in the text is summarized as follows:
Weakening the triplet-triplet annihilation (TTA) self-quenching effect induced by sensitizers remains a tremendous challenge due to the very few investigations carried out on them. Herein, benzo-21-crown-7 (B21C7)-functionalized 2,6-diiodo-1,3,5,7-tetramethyl-8-phenyl-4,4-difluoroboradiazaindacene (DIBDP) was synthesized to investigate the influences of huge bulks and electron-rich cavities of B21C7 moieties on the fluorescence emission and triplet-state lifetimes of DIBDP moieties. D. functional theory (DFT)/time-dependent DFT (TDDFT) computable results preliminarily predicted that B21C7 moieties had influences on the fluorescence emissions of DIBDP moieties but not on their localization of triplet states of B21C7-functionalized DIBDP (B21C7-DIBDP). The UV-vis absorption spectra, fluorescence emission spectra, and cyclic voltammograms verified that there was an electron-transfer process from the B21C7 moiety to the DIBDP moiety in B21C7-DIBDP. However, the calculated results of ΔGCS and ECS values and nanosecond time-resolved transient absorption spectra demonstrated that the electron-transfer process from the B21C7 moiety to the DIBDP moiety in B21C7-DIBDP had direct influences on the fluorescence emission of DIBDP moieties but not on the triplet states of DIBDP moieties. The exptl. values of triplet-state lifetimes of B21C7-DIBDP were obviously longer than those of DIBDP at a high concentration (1.0 x 10-5 M); however, the fitted values of intrinsic triplet-state lifetimes of B21C7-DIBDP were slightly greater than those of DIBDP in the same solvent. These results demonstrated that the steric hindrance of B21C7 moieties could weaken the TTA self-quenching effect of DIBDP moieties at a high concentration and the a-PET effect induced a proportion of the produced singlet states of DIBDP moieties and could not emit fluorescence in the form of radiation transition but they could be transformed into triplet states through intersystem crossing (ISC) processes due to the iodine atoms in the DIBDP moiety. The stronger a-PET effects in polar solvents induced smaller fluorescence quantum yields so that more singlet states of DIBDP moieties were transformed into triplet states to weaken the TTA self-quenching effects. After reading the article, we found that the author used 1-Iodopyrrolidine-2,5-dione(cas: 516-12-1Safety of 1-Iodopyrrolidine-2,5-dione)
1-Iodopyrrolidine-2,5-dione(cas: 516-12-1) is used in the preparation of vinyl sulfones from olefins and benzenesulfinic acid. It acts as a source for I+ and involved in Hunsdiecker reactions for the conversion of cinnamic acids, and propiolic acids to the corresponding alfa-halostyrenes and 1-halo-1-alkynes respectively. Safety of 1-Iodopyrrolidine-2,5-dione
Referemce:
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com