7-二乙胺基-3-[(噻吩-2-亚甲氨基)甲基]香豆素的合成及对Fe^(3+)的荧光识别

Synthesis and Fluorescence Sensing for Fe^(3+) Using 7-(Diethylamino)-3-(((thiophen-2-ylmethyl)imino) methyl)-2H-chromen-2-one

以7-二乙胺基-3-醛基香豆素为原料,与2-噻吩甲胺反应,生成一种新型的7-二乙胺基-3-[(噻吩-2-亚甲氨基)甲基]香豆素(DTMC),分别使用了~1H NMR、红外光谱和元素分析表征其结构,并研究了该分子探针DTMC对金属离子的光学传感识别。结果发现向分子探针DTMC的DMF溶液中加入适量的Fe^(3+),可以观察到其荧光明显地减弱。而且当加入Fe^(3+)的量达到饱和浓度10^(-3) mol/L后,DTMC甚至会产生荧光"关"的效果。其它金属阳离子几乎不会对分子探针DTMC选择性识别Fe^(3+)造成干扰。根据荧光光谱数据计算出DTMC与Fe^(3+)的结合常数为4.04×10~3(mol/L)^(-1),而根据Job图分析出两者之间以2∶1的摩尔比配位。

A new fluorescent coumarin-based Schiff-base compound,7-(diethylamino)-3-(((thiophen-2-ylmethyl)imino)methyl)-2 H-chromen-2-one(DTMC),was synthesized and characterized by elemental analyses,1H NMR,FTIR and fluorescence spectrum,respectively.It was evaluated as a chemoselective Fe3+sensor.Addition of Fe3+into DMF solution of DTMC could reduce the fluorescence intensity of DTMC.Moreover,the fluorescence of DTMC would be turned off while the amount of Fe3+reached to saturated concentration of 10-3 mol/L.The sensor was selective for Fe3+over other ions.The binding constant between DTMC and Fe3+was calculated for 4.04×103(mol/L)-1.The molar ratio of this complex was 2∶1 according to Job analysis.