Multi-addressable photochromic terarylene containing benzo[b]thiophene-1,1-dioxide unit as ethene bridge: multifunctional molecular logic gates on unimolecular platform
作者:Shangjun Chen、Yuheng Yang、Yue Wu、He Tian、Weihong Zhu
DOI:10.1039/c2jm14973g
日期:——
A photochromic terarylene (BTO) containing a benzo[b]thiophene-1,1-dioxide unit as a central ethene bridge was synthesized and characterized, and exhibits good thermal stability and fatigue resistance both in solution and bulk crystals. When triggered by chemical ions, protons and light, BTO can behave as an absorbance and fluorescence switch, leading to a multi-addressable system. The different color changes of BTO upon adding Cu2+ and Hg2+ ions arise from the relative binding stoichiometry and the association affinities. The titration of the Job plot indicates that BTO forms a 1 : 1 complex with Hg2+, whereas in the case of Cu2+, the Job plot exhibits a maximum at about a 0.33 mole fraction, indicating that BTO forms a 2 : 1 complex with Cu2+. Moreover, the conversion yield of BTO can be modulated with chemical ions. Impressively, an increase in conversion yield was observed by adding Hg2+ to the solution of BTO, that is, the conversion yield and cyclization quantum yield are increased from 77.6% and 28.5% (for BTO only) to 99.8% and 43.1% (BTO-Hg2+), respectively. A series of molecular logic gates such as a half-adder, half-subtractor, 4-to-2 encoder, 2-to-4 decoder, and a 1 : 2 demultiplexer were constructed on the unimolecular platform by employing absorption and emission properties at different wavelengths as outputs, with the appropriate combination of chemical and photonic stimuli, which is a further step towards data processing on the molecular level with potential applications in sensing and labeling as well as for data manipulation.
合成并表征了含有苯并[b]噻吩-1,1-二氧化物单元作为中心乙烯桥的光致变色三萘嵌苯(BTO),其在溶液和块体晶体中均表现出良好的热稳定性和抗疲劳性。当被化学离子、质子和光触发时,BTO 可以充当吸光度和荧光开关,从而形成多寻址系统。添加 Cu2+ 和 Hg2+ 离子后,BTO 的不同颜色变化源于相对结合化学计量和缔合亲和力。 Job 图的滴定表明 BTO 与 Hg2+ 形成 1 : 1 络合物,而对于 Cu2+,Job 图在摩尔分数约为 0.33 处出现最大值,表明 BTO 与 Cu2+ 形成 2 : 1 络合物。此外,BTO的转化率可以用化学离子调节。令人印象深刻的是,通过向BTO溶液中添加Hg2+,观察到转化产率的增加,即转化产率和环化量子产率从77.6%和28.5%(仅BTO)增加到99.8%和43.1%(BTO- Hg2+),分别。利用单分子平台上的吸收和发射特性,在单分子平台上构建了一系列分子逻辑门,例如半加器、半减器、4对2编码器、2对4解码器和1 : 2解复用器。不同波长作为输出,并适当组合化学和光子刺激,这是在分子水平上进行数据处理的又一步,在传感和标记以及数据操作方面具有潜在的应用。