BODIPY荧光二向性液晶染料的制备及性能

以8-(4-碘苯基)氟硼吡咯为原料,与4-乙炔基苯基胆甾醇酯或4-乙炔基苯戊基双环己基甲醇酯进行Sonogashira偶联反应,制备了两个含氟的荧光二向性液晶染料DC-1和DC-2,其化学结构均由1HNMR、13CNMR和HRMS鉴定。将染料DC-1和DC-2进行光谱测试,最大吸收波长和最大发射波长分别在503和517 nm,发亮绿色荧光。基于宾-主(G-H)效应,将染料DC-1和DC-2作为宾体组分溶于主体液晶E7中,测得DC-2在液晶E7中的吸收二向色比高达8.91,有序参数为0.73,可应用在宾-主型液晶显示器(GH-LCD)中。经差热扫描量热仪(DSC)测试,染料DC-1和DC-2在一定温度范围内具有介晶性质,并通过偏光显微镜(POM)验证了DC-1和DC-2的液晶织构。

Preparation and properties of BODIPY fluorescent dichroic liquid crystal dyes

Two fluorinated fluorescent dichroic liquid crystal dyes DC-1 and DC-2 were synthesized through the Sonogashira coupling reaction by the raw materials of 8-(4-iodophenyl) fluoroboropyrrol and the 4-acetylphenylcholesterol ester or 4-acetylphenylpentyl dicyclohexyl methanol ester. Their chemical structures were both identified by 1H NMR, 13C NMR and HRMS. After the spectrum test conducted on the dye DC-1 and DC-2, the maximum absorption and emission wavelengths of dye DC were 503 and 517 nm respectively, the dye DC emitted green fluorescence. Based on the Guest-Host (G-H) effect, dye DC was dissolved in the host liquid crystal E7 as the guest component, the absorption dichroic ratio of DC-2 in the host liquid crystal E7 was as high as 8.91, and the ordered parameter was 0.73 which can be used in the Guest-Host liquid crystal display (GH-LCD). The mesomorphic properties of dye DC were tested by differential scanning calorimeter (DSC) in a certain temperature range. The liquid crystal texture of dye DC was verified by polarizing microscope (POM).