α-单取代吡啶盐的新方法合成及光化学反应研究

Synthesis of α-Monosubstituted Pyridinium Salts and Their Photochemical Reaction

以α位单取代2,4,5-三苯基吡喃盐和取代伯胺为原料,一步合成出相应的α位单取代吡啶盐.在此基础上研究了α位单取代吡啶盐的光化学反应,成功合成出具有较高共平面结构的菲啶盐.通过测定吡啶盐和菲啶盐的荧光光谱发现,N位苯环上取代基供电性的增强使得吡啶盐荧光发射光谱发生明显的红移,荧光强度减弱,而菲啶盐由于分子共平面性增强极大提高了分子的荧光强度.

The novel one-pot reaction of α-monosubstituted 2,4,5-triphenylpyrylium perchlorate with substituted primary amines was proved to give the corresponding α-monosubstituted pyridinium salts in high yield.New phenanthridinium salt was synthesized via photochemical reaction of α-monosubstituted pyridinium salts.The photophysical properties of compounds were investigated by UV-Vis and fluorescent spectroscopy.It was found that increase of electron donating ability of N-substituents induced the clear red shift of the emission spectra and the decrease of the fluorescence intensity.Furthermore,the more planarity of phenanthridinium salt compared to pyridinium salt extremely enhanced the fluorescence intensity.