Seki Tomohiro, Jin Mingoo, Ito Hajime
Division of Applied Chemistry & Frontier Chemistry Center, Faculty of Engineering, Hokkaido University , Sapporo, Hokkaido 060-8628, Japan.
Inorg Chem. 2016 Dec 5;55(23):12309-12320. doi: 10.1021/acs.inorgchem.6b02107. Epub 2016 Nov 15.
Luminescent compounds that are sensitive to volatile organic solvents are useful for detection of harmful gases. Although such compounds have been reported, discrimination of various types of volatile organic compounds using one compound remains challenging. We reported a series of gold isocyanide complexes that form various crystalline structures with distinct emission properties, which can be interconverted by mechanical stimulation and solvent addition. Here, we report that introduction of a biphenyl unit into a gold isocyanide scaffold (denoted complex 3) enables discrimination of various volatile organic compounds by forming 11 solvent-containing crystal structures 3/solvent [solvent can be CHCl, pyridine (Py), CHCl, CHBr, dimethylacetamide (DMA), acetaldehyde (AcH), CHCN, DMF, (S)-propylene oxide (SPO), rac-propylene oxide (racPO), or acetone] with different emission properties (emission maxima of 490-580 nm). Mechanical stimulation of 3/solvent affords amorphous 3 without solvent inclusion. The resulting 3 can again detect volatile compounds by forming 3/solvent with concomitant emission color changes. We also afforded a dozen single crystals of 3, which include 11 solvated 3/solvent and one solvent-free 3/none. The molecular arrangements of 3 in 3/solvent and 3/none are all different. Comparison of various crystallographic parameters of 3/solvent and 3/none with their corresponding optical properties indicates that a combination of various structural properties of 3 affects the optical properties of 3. This study reveals that the introduction of a biphenyl moiety could be a useful design to develop versatile indicators for solvents through the formation of multiple luminescent crystal structure.
对挥发性有机溶剂敏感的发光化合物可用于有害气体的检测。尽管已经报道了此类化合物，但使用一种化合物来区分各种类型的挥发性有机化合物仍然具有挑战性。我们报道了一系列异氰基金配合物，它们形成了具有不同发射特性的各种晶体结构，这些结构可通过机械刺激和添加溶剂进行相互转化。在此，我们报道在异氰基金支架中引入联苯单元（标记为配合物3）能够通过形成11种含溶剂的晶体结构3/溶剂[溶剂可以是CHCl、吡啶（Py）、CHCl、CHBr、二甲基乙酰胺（DMA）、乙醛（AcH）、CHCN、DMF、（S）-环氧丙烷（SPO）、外消旋环氧丙烷（racPO）或丙酮]来区分各种挥发性有机化合物，这些结构具有不同的发射特性（发射最大值为490 - 580 nm）。对3/溶剂进行机械刺激可得到不含溶剂包合物的无定形3。所得的3可以通过再次形成3/溶剂并伴随发射颜色变化来检测挥发性化合物。我们还得到了12个3的单晶，其中包括11个溶剂化的3/溶剂和1个无溶剂的3/无溶剂。3在3/溶剂和3/无溶剂中的分子排列均不同。对3/溶剂和3/无溶剂的各种晶体学参数与其相应光学性质的比较表明，3的各种结构性质的组合会影响3的光学性质。这项研究表明，引入联苯部分可能是一种有用的设计，可通过形成多种发光晶体结构来开发通用的溶剂指示剂。
