Cruciform Fluorophores

在有机化学和大分子化学程序的支持下，Uwe Bunz教授提出了一种新型的十字形发色团(XF，十字形，1，4-双(芳基-乙炔基)-2，5-二苯基苯)，其中的前线分子轨道位于两个不同的轴上。最高占位分子轨道(HOMO)位于二芳基苯轴上，最低空位分子轨道(LUMO)位于双芳乙炔基的横轴上。这种轨道排列将电子性质转化为空间模式；XF将在二芳基苯轴上含有金属配位给电子取代基，在双(芳乙炔)轴上含有金属配位受体，实现对不同金属阳离子的两级传感。两个分析物的相加以及由此产生的荧光变化将被用来构建逻辑表。分析物是输入，而荧光改变了输出。他们计划将含金属盐和不含金属盐的XF沉积到固体载体上，以获得挥发性有机化合物的传感器阵列。不同荧光团的组合和使用与不同金属络合的同一荧光团，在暴露于挥发胺等分析物时，由于可逆解配/质子化或去质子化，将导致发射性质的变化。更广泛的影响：这种化学可能允许使用浸渍不同XF型荧光团的简单试纸来检测水中的有毒金属离子和大气中的有毒挥发胺。这项研究将开发一种基于XF识别不同分析物的分子逻辑，用于分子计算。教育影响：PI与市中心的一所高中(三城高中)开展了积极的外展计划。他已经并将让高中生在他的实验室里使用XF和/或XF溶液固定在固体载体(如高度硅烷化的硅胶)上进行模型分析物的传感工作，以吸引聪明的学生进入化学。

With the support of the Organic and Macromolecular Chemistry Program, Professor Uwe Bunz has proposed a new type of cross-shaped chromophore (XF, cruciform, 1,4-bis(aryl-ethynyl)-2,5-distyrylbenzenes) in which the frontier molecular orbitals are localized on the two different axes. The Highest Occupied Molecular Orbital (HOMO) is localized on the distyrylbenzene axis, while the Lowest Unoccupied Molecular Orbital (LUMO) is localized on the bis(arylethynyl) transverse. This orbital arrangement translates electronic properties into spatial patterns; the XFs will contain metal coordinating electron-donating substituents on the distyrylbenzene axis and metal coordinating acceptors on the bis(arylethynyl) transverse achieving two-stage sensing of different metal cations. The addition of two analytes with the resulting fluorescence changes will be used to construct a Logic Table. The analytes are the input and the fluorescence change the output. They plan to deposit the XFs with and without metal salts onto solid supports to obtain sensor arrays for volatile organic compounds. The combination of different fluorophores and the use of the same fluorophore complexed with different metals will lead to changes in emissive properties when exposed to analytes such as volatile amines due to reversible decomplexation/protonation or deprotonation. Broader Impact: This chemistry will potentially allow detecting toxic metal ions in water and toxic volatile amines in the atmosphere using simple test strips impregnated with different XF-type fluorophores. The research will develop a molecular logic based upon recognition of different analytes with XFs for molecular computing. Educational Impact: The PI has an active outreach program with an inner city high school (Tri-Cities High). He has had and will have high school students in his laboratory working on the sensing of model analytes using either solutions of XFs and/or XFs immobilized on solid supports such as highly silanized silica gel to attract bright students into chemistry.