Xiao-xiao Zhang

Synthesis, spectroscopic characteristic of novel fluorescent dyes of pyrazoline compounds

Four novel fluorescence dyes of the pyrazoline were synthesized and fully characterized by means of (1)H, (13)C NMR, and HRMS. The optical, electrochemical properties were also investigated. Solvent effect on the fluorescence characteristics of the four compounds indicates that the emission wavelength was red-shifted with the increase of solvent polarity. As we expected, the results indicated that these compounds exhibited high quantum yields. Quantum chemical calculations were used to obtain optimized ground-state geometry, spatial distributions of the HOMO, LUMO levels of the compounds.

Synthesis and characteristics of novel fluorescence dyes based on chromeno[4,3,2-de][1,6]naphthyridine framework

A series of entirely new framework chromeno[4,3,2-de][1,6]naphthyridine derivatives containing carbazole groups have been carefully designed and prepared. The relationship of photoluminescence property and structure of these compounds was systematically investigated via UV-vis, fluorescence and electrochemical analyzer. The HOMO and LUMO distributions of these compounds were calculated by density functional theory (DFT) (B3LYP; 6-31G(∗)) method. These compounds exhibited high fluorescence quantum yields, desirable HOMO levels and high thermal stability, indicating that the combination of chromeno[4,3,2-de][1,6]naphthyridine and carbazole could be an efficient means to enhance hole-transporting ability and fluorescent quantum yield.

Glucose-containing imidazolium salt-catalyzed cross-aldol reaction of isatins and unactivated ketones

Ketone–ketone cross-aldol reaction of isatins and unactivated ketones was catalyzed by glucose-containing imidazolium salt β-1-imidazole-2,3,4,6-tetra-o-hydroxy-d-glucopyranosyl bromide in neutral condition to generate 3-alkyl-3-hydroxyindolin-2-ones in excellent yield.