基于汞离子促进硫羰基脱硫的不可逆反应，合成了两种分别含有丙烯酰基酰肼基硫脲基团和丙烯基酰肼基硫脲基团的罗丹明B荧光探针（RhBHA和RhBCH），用以高选择性、高灵敏度检测水溶液中的Hg^2＋离子．通过荧光发射光谱和可见光下颜色变化研究了硫羰基所处的化学环境对汞离子促进的脱硫反应的影响．研究结果表明，引入罗丹明B荧光生色团后，分子的“开环一闭环”转换过程与分子内氢键作用没有相互影响，分子内氢键加速了汞离子的脱硫反应，伴随“开环一闭环”转换过程的颜色变化通过肉眼即可观察到．此外，还研究了分子问氢键作用对脱硫反应速率的影响．通过加入汞离子后荧光强度随时间变化的跟踪发现，若溶剂与RhBHA形成分子问氢键作用，会使汞离子诱导的脱硫反应有所迟缓．这种分子间的氢键作用，对能促进快速脱硫反应的分子内氢键作用产生影响．%Based on the irreversible desulfurization ofthiocarbonyl promoted by mercury ions, two kinds of chemodosimeters of Rhodamine B derivatives as fluorescent probe respectively containing propylene acyl thiourea group and the propenyl thiourea group （RhBHA and RhBCH） were synthesized. They were used for the detection of Hg^2＋ ions in aqueous solutions with high selectivity and high sensitivity. According to the fluorescence emission spectra and the colorimetric analysis under visible light, the influence of the chemical environment of thiocarbonyl groups on the desulfurization by mercury ions was studied. The results showed that there was no influence between the ring ＂open-close＂ transformation and the intramolecular hydrogen bond. The intramolecular hydrogen bonds increased the susceptibility of RhBHA toward desulfurization by mercury ions. With the molecular ring ＂open-close＂ transformation, the color change can be observed by the naked eye. In addition, we also studied the influence of the solvent intermolecular hydrogen bonding on the rate of desulfurization. By trace of the fluorescence intensity changes of RhBHA for Hg2＋ at different time interval, it was found that the formation of intermolecular hydrogen bond between the solvents and RhBHA could make the desulfurization rate slow-down.
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