【作者】 付梅艳；

【导师】 肖义；

【作者基本信息】 大连理工大学 ， 精细化工， 2009， 博士

【摘要】 目前,以萘酰亚胺和罗丹明为基础衍生得到的荧光染料凭借其优越的光化学和光物理性能吸引了众多研究者们的目光,萘酰亚胺类荧光染料在多个领域当中具有巨大的应用空间,因此开发更多性能优越的此类荧光染料是我们当前面临的重要机遇与挑战。另外随着罗丹明类长波长荧光染料在生物环境中越来越多的应用,对其种类的需求日益增长,因此开发新型性能优越的罗丹明类长波长荧光染料已成为当前科学家们急需解决的重要课题。鉴于上述考虑,本论文设计并合成了三种作为探针用途的萘酰亚胺类荧光染料和一种硅杂罗丹明类长波长荧光染料。1.利用良好的质子受体N¹,N¹,N⁸,N⁸-双二甲基-1,8-二胺基萘（DMAN）设计并合成了三个基于PET机理的萘酰亚胺类荧光质子海绵A1、A2和A3,结果表明它们能够在低浓度质子环境下捕获质子。尤其是质子海绵A3,其对质子的最低检测浓度为1.25×10^-13mol/L（即pH=12.9）。计算得到其pKa为11,实现了极低浓度下对质子的荧光识别。2.利用FRET机理设计并合成了基于萘酰亚胺和方酸双荧光团氟离子荧光探针SN-1、SN-2和SN-3,打破了常规氟离子识别模式,该类型探针将能量转移和化学反应性识别有机结合起来,利用化学反应破坏一个荧光团来抑制能量转移实现对氟离子离子的双波长比例荧光检测。其中SN-2和SN-3对氟离子有很好的识别性能,利用吸收和荧光光谱中双波长的比例变化可以实现量化检测。SN-2对氟离子检测所用时间非常短,仅为3min,其检测氟离子的最低浓度为2μM（0.2倍摩尔当量）,平衡浓度为1.2 mM。SN-3对氟离子检测时间为30 min,检测最低浓度为1μM（0.1倍摩尔当量）,平衡浓度为50μM。3.通过在萘酰亚胺4-位上引入手性官能团合成了两个手性荧光探针NNH和NNM。其中NNH能够通过吸收光谱的蓝移和荧光光谱的增强与蓝移识别D-扁桃酸,对L-扁桃酸没有响应;而NNM则能够通过荧光光谱和圆二色光谱识别质子,利用这两种方法得到其pKa值分别为8.5和8.8,二者非常吻合,证明利用圆二色光谱研究NNM对pH的响应是可行的。4.利用硅原子作为功能性原子,设计并合成了两个新型硅杂罗丹明类长波长荧光染料TMDHS和TMDPS,它们的最大吸收峰分别位于641nm和628nm,荧光发射峰分别位于659 nm和664 nm。相对于哌罗宁Y,由单一桥原子的改变使其吸收和荧光波长红移了90 nm以上。据我们所知这是首次利用硅原子作为功能性元素来调控荧光染料的光谱性能。通过电化学方法和理论计算证明了硅原子相对氧原子强的供电子能力提高了其HOMO能级,特殊的δ^*-π^*共轭作用降低了其LUMO能级,二者的协同作用大大减小了能隙能量,使吸收和荧光光谱明显红移。更多还原

【Abstract】 The naphthalimides and rhodamines have had great attention because of their good photochemical and photophysical properties.Naphthalimides had large potential application market in various fields,so it was a chance and a challenge for us to develop more functional derivatives of naphthalimide with better properties.Since the extentisively appilication of rhodamines in bioliogical environment,it was necessary and urgent to develop more kinds of such long wavelength rhodamine derivatives to meet the increasing demands.In this work, three kinds of fluorescent sensors based on naphthaiimdes and one kind of silicon-substituted rhodamine dyes with long absorption and emission wavelength had been synthsized.1.The new PET fluorescent proton sponges-A1,A2 and A3 had synthesized based on naphthalimides.DMAN was proved a good proton receptor unit to develop sensitive fluorescent switches triggered by lower-concentration proton.A3 exhibited significant fluorescence enhancement upon protonation in high pH（pH=12.9） aqueous solutions,the pKa of which was 11.The lowest detection concentrition was 1.25×10^-13 mol/L.2.Based on the approach of switching off FRET by wrecking the acceptor part, cassette-type sensors（SN-1,SN-2 and SN-3） for fluoride anion containing naphthalimide and squaraine units has been developed.These sensors show sensitive response to fluoride anion through both naked-eye detectable colour changes and ratiometric fluorescence changes.The detection process was realized by the combination of the reactive recognition and FRET mechanism.SN-2 and SN-3 showed excellent ratiometric fluorescence changes which made the quantitive measurement to be avaliable.The detection limit and equilibrium concentrion of F^- for SN-2 was 2μM and 1.2 mM with short reaction time（3min）.The detection limit and equilibrium concentrion of F^- for SN-3 was 1μM and 50μM with the reaction time about 30min.3.Two chiral fluorephores NNH and NNM had been synthesized by introducing the chiral center into 4-position of the naphthalimide.NNH can be used as the mandelic acid sensor.The absorption and emission of NNH blue shifted 12 nm with the addition of the D-mandelic acid,as same time the emission increased to 1.2 flod.The absorption and emission of NNH had no changes with the addition of L-mandelic acid.The NNM can be used as pH sensor by fluorescent emission and circular dichroism properties,the pKa caculated by the two menthods were 8.5 and 8.8 respectively,which machted very well.It proved that circular dichroism could be used as a reasonable method for NNM to detect the recognition of pH.4.Two new strong fluorescence silicon-substituted rhodamine dyes TMDHS and TMDPS,in the red region had been developed through substitution of rhodamine’s oxygen bridge atom by silicon.Such a small structural change resulted in a 90 nm red shift.The absorption wavelength of the two compounds was at 641 nm and 628 nm respectively.The emission wavelength of which was at 659nm and 664nm respectively.As we known,this was the first case that silicon atom was adopted as the functional element into the key position of a conventional excellent dye to successfully modulate the spectral properties.The electrochemical and the theoretical computational studies indicated that the smaller energy gap of TMDHS resulted from both energy decrease of LUMO attributed to specialδ^*-π^* and energy increase of HOMO attributed to the electron donating ability of silicon atom.更多还原