联二噻吩稠合的近红外BODIPY染料的合成与光谱性质

摘要

以叠氮乙酸乙酯和联二噻吩甲醛为原料,合成了联二噻吩并吡咯单体,之后在酸催化下与4-N,N-二甲基氨基苯甲醛缩合并与三氟化硼配位,得到一个新型的BODIPY染料SY.采用1H NMR、质谱以及元素分析对其结构进行了表征.化合物SY在二氯甲烷中的最大吸收和发射波长分别为654和689 nm;采用荧光光谱滴定方法研究了它对pH值的响应,酸性条件下N,N-二甲基苯氨基团发生质子化,抑制了光诱导电子转移对BODIPY母体的荧光淬灭,其溶液的荧光显著增强,染料SY可以作为近红外的pH值荧光探针.%A bithiophene-fused BODIPY (SY) dye is synthesized via acid catalyzed condensation of thiophene substituted thienopyrrole and 4-N,N-dimethylaminobenzaldehyde,followed by treatment with boron trifluoride diethyl ether.The structure of SY has been characterized by 1H NMR,mass and elemental analysis.The absorption and emission bands of SY are centered at 654 nm and 689 nm in CH2Cl2,respectively.Fluorometric titration experiment shows that the fluorescence intensity is enhanced upon protonation of the electron donating N,N-dimethylamino group,suggesting that SY can be used as a NIR fluorescence probe for pH value.