Synthesis and two-photon absorption properties of novel 2-substituted-4,5-diphenyl-1H-imidazoles

Autor: Yupeng Tian, Yu-Lu Pan, Guo-Chuang Zheng, Yan-Tao Zhou, Li Bai, Zhi-Bin Cai, Shengli Li
Rok vydání: 2016
Předmět:
Zdroj: Tetrahedron. 72:2988-2996
ISSN: 0040-4020
DOI: 10.1016/j.tet.2016.04.015
Popis: Novel 2-substituted-4,5-diphenyl-1H-imidazoles (M1–M4) were synthesized via a three-component, one-pot reaction under solvent-free conditions. The structures were characterized by infrared, hydrogen-1 nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, mass spectrometry and elemental analysis. Their UV-visible absorption, single-photon excited fluorescence, two-photon absorption, and two-photon excited fluorescence were systematically investigated in different solvents. Pumped by femtosecond laser pulses, M1 and M4 exhibit large two-photon absorption cross-sections (585 and 1193 GM in DMF, respectively). The quantum chemical density functional theory calculations offer complementary information regarding the frontier orbitals and the molecular structures, which confirm that the degree of intramolecular charge transfer plays an important role in enhancing two-photon absorption properties.
Databáze: OpenAIRE