121848-75-7Relevant articles and documents
Investigations of the heavy atom effect occurring in bianthryl and 10,10′-dibromobianthryl. Fluorescence, cyclovoltamperometric and actinometric studies
Mac, Marek,Danel, Andrzej,Kizior, Katarzyna,Nowak, Pawel,Karocki, Andrzej,Tokarczyk, Bogdan
, p. 988 - 997 (2003)
A preliminary study of photophysical and photochemical properties of 9,9′-bianthryl (BA) and 10,10′-dibromo,9,9′-bianthryl (DBrBA) is presented. Dual fluorescence occurring in bianthryl (BA) has been investigated in solvents containing heavy atoms, such as chlorine, bromine and iodine. The presence of heavy atoms reduces strongly the fluorescence lifetimes and the fluorescence quantum yields of BA, the effect is strongest in ethyl iodide, i.e. in the solvent containing the heaviest atom, iodine. On the other hand, it has been found that introduction of two heavy atoms (bromine) into the bianthryl molecule modifies noticeably its fluorescence properties, which indicates existance of an internal heavy atom effect. Again, a reduction of the fluorescence lifetime and the fluorescence quantum yield, compared to the parent molecule, has been observed. On the basis of these observations the mechanism of 1CT ?3LE intersystem crossing has been discussed. In BA the rate determining process is a reversible spin inversion within the radical pair. In DBrBA where the spin flip is accelerated by the presence of heavy atoms (bromines) the spin-allowed electron transfer 3CT ?3LE becomes important in the overall intersystem crossing process. It has been found that DBrBA undergoes a photoreduction in the presence of aromatic donors, such as amines, leading finally to BA. Similar reaction seems to be observed in electrochemical measurement. The reduction of DBrBA originates from the primary electron transfer process either photoinduced or electrochemical leading to the free anion radicals of DBrBA.
Photoinduced C-C reactions on insulators toward photolithography of graphene nanoarchitectures
Palma, Carlos-Andres,Diller, Katharina,Berger, Reinhard,Welle, Alexander,Bj?rk, Jonas,Cabellos, Jose Luis,Mowbray, Duncan J.,Papageorgiou, Anthoula C.,Ivleva, Natalia P.,Matich, Sonja,Margapoti, Emanuela,Niessner, Reinhard,Menges, Bernhard,Reichert, Joachim,Feng, Xinliang,R?der, Hans Joachim,Klappenberger, Florian,Rubio, Angel,Müllen, Klaus,Barth, Johannes V.
, p. 4651 - 4658 (2014)
On-surface chemistry for atomically precise sp2 macromolecules requires top-down lithographic methods on insulating surfaces in order to pattern the long-range complex architectures needed by the semiconductor industry. Here, we fabricate sp2-carbon nanometer-thin films on insulators and under ultrahigh vacuum (UHV) conditions from photocoupled brominated precursors. We reveal that covalent coupling is initiated by C-Br bond cleavage through photon energies exceeding 4.4 eV, as monitored by laser desorption ionization (LDI) mass spectrometry (MS) and X-ray photoelectron spectroscopy (XPS). Density functional theory (DFT) gives insight into the mechanisms of C-Br scission and C-C coupling processes. Further, unreacted material can be sublimed and the coupled sp2-carbon precursors can be graphitized by e-beam treatment at 500 °C, demonstrating promising applications in photolithography of graphene nanoarchitectures. Our results present UV-induced reactions on insulators for the formation of all sp 2-carbon architectures, thereby converging top-down lithography and bottom-up on-surface chemistry into technology.
Co-crystals of 9,9′-bianthracene-10,10′-dicarboxylic acid with linear bidentate basic ligand molecules: Synthesis, crystal structure, and properties based on the layer structure exfoliated by water
Azumaya, Isao,Hikawa, Hidemasa,Kikkawa, Shoko,Okayasu, Misaki
, p. 497 - 505 (2020/01/29)
Co-crystals of 9,9′-dianthracene-10,10′-dicarboxylic acid (1) with the linear bidentate bases 9,9′-biacridine (bac), phenazine (phez), 4,4′-dipyridine (dpy), and DABCO (dabco) were synthesized. In the crystal structures of the co-crystals of 1 and bac, phez, and dpy, one-dimensional (1D) structures were formed through the hydrogen bonding between the acid and the base. For each combination of the acid and the bases, several kinds of polymorphic co-crystals with a similar structure were obtained. Among them, a combination of 1 and dabco gave three kinds of co-crystals which had a layered structure. In one of the co-crystals, a phenomenon where layers of the crystals could be exfoliated by dropping water was observed. The two-dimensional (2D) fingerprinting plot of the co-crystals showed that the major interaction to form the 1D structure was O-H?N hydrogen bonding and that to form the layered structure was the CH-π interaction, and the influence of the latter interaction on the robustness of the crystal was stronger than the former in the co-crystals.
A new thiosemicarbazone fluorescent probe based on 9,9′-bianthracene for Hg2+ and Ag+
Chen, Zhen-E,Zhang, Hai,Iqbal, Zafar
, p. 34 - 40 (2019/03/04)
A new 9,9′-bianthracene-based thiosemicarbazone (D1) has been successfully synthesized and utilized for chemosensors. The properties of D1 were systematically investigated by UV–Vis, fluorescence titration and theoretical calculations. As a result, D1 exhibits a characteristic fluorescence quenching phenomenon in the presence of Hg2+ or Ag+ compared to other metal cations (Na+, K+, Mg2+, Ba2+, Al3+, Zn2+, Fe2+, Pb2+, Cu2+, Co2+, Cd2+, Ni2+ and Mn2+). The detection limits of Hg2+ and Ag+ reach 6.62 × 10?7 M and 1.99 × 10?5 M, respectively. This is mainly attributed to the Hg2+ (or Ag+) forms a stable five-membered ring with the N atom in Schiff base C[dbnd]N and the S atom in thiourea. The results suggest that the probe D1 is a promising candidate for chemosensors in aqueous media due to its highly selectivity for Hg2+ and Ag+.