Shekhovtsov, Nikita A. published the artcileA 1-Hydroxy-1H-imidazole ESIPT Emitter Demonstrating anti-Kasha Fluorescence and Direct Excitation of a Tautomeric Form, Safety of Picolinonitrile, the main research area is hydroxy imidazole preparation fluorescence crystal structure ESIPT; computational chemistry; heterocycles; hydrogen bonds; photochemistry; tautomerism.
The ability of 1-hydroxy-1H-imidazoles to exist in the form of two prototropic tautomers, the N-hydroxy and the N-oxide forms, can be utilized in the design of new types of ESIPT-fluorophores (ESIPT=excited state intramol. proton transfer). Here we report the first example of 1-hydroxy-1H-imidazole-based ESIPT-fluorophores, 1-hydroxy-5-methyl-2,4-di(pyridin-2-yl)-1H-imidazole (HL), featuring a short intramol. hydrogen bond O-H···N (O···N 2.56 Å) as a pre-requisite for ESIPT. The emission of HL originates from the anti-Kasha S2→S0 fluorescence in the N-oxide form as a result of a large S2-S1 energy gap slowing down the S2→S1 internal conversion. Due to an energy barrier between the N-hydroxy and N-oxide forms in the ground state, the HL mols. can be trapped and photoexcited in the N-oxide form leading to the Stokes shift of ca. 60 nm which is the smallest among known ESIPT-fluorophores.
ChemPlusChem published new progress about Conical intersection. 100-70-9 belongs to class nitriles-buliding-blocks, name is Picolinonitrile, and the molecular formula is C6H4N2, Safety of Picolinonitrile.
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts