Lehrstuhl für Anorganische Chemie und Strukturchemie, Universität Bielefeld, Fakultät für Chemie, Universitätsstrasse 25, 33615 Bielefeld (Germany) http://www.uni-bielefeld.de/chemie/arbeitsbereiche/ac3-mitzel/
Angew Chem Int Ed Engl. 2014 Jul 21;53(30):7938-42. doi: 10.1002/anie.201402145. Epub 2014 Jun 12.
The formation of host-guest (H-G) complexes between 1,8-bis[(diethylgallanyl)ethynyl]anthracene (H) and the N-heterocycles pyridine and pyrimidine (G) was studied in solution using a combination of NMR titration and diffusion NMR experiments. For the latter, diffusion coefficients of potential host-guest structures in solution were compared with those of tailor-made reference compounds of similar shape (synthesized and characterized by NMR, HRMS, and in part XRD). Highly dynamic behavior was observed in both cases, but with different host-guest species and equilibria. With increasing concentrations of the pyridine guest, the equilibrium H2⇄H2κ(1)-G1⇄HG2 is observed (in the second step a host dimer coordinates one guest molecule); for pyrimidine the equilibrium H2→H1κ(2)-G1⇄HG2 is observed (the formation of a 1:1 aggregate is the second step).
在溶液中，通过 NMR 滴定和扩散 NMR 实验的组合，研究了 1,8-双[(二乙基胂基)乙炔基]蒽（H）与吡啶和嘧啶（G）的 N-杂环之间的主客体（H-G）配合物的形成。对于后者，比较了潜在主客体结构在溶液中的扩散系数与类似形状的定制参考化合物的扩散系数（通过 NMR、高分辨率质谱和部分 XRD 合成和表征）。在这两种情况下都观察到了高度动态的行为，但具有不同的主客体物种和平衡。随着吡啶客体浓度的增加，观察到平衡 H2 ⇄ H2κ(1)-G1 ⇄ HG2（在第二步中，一个主体二聚体配位一个客体分子）；对于嘧啶，观察到平衡 H2 → H1κ(2)-G1 ⇄ HG2（第二步是形成 1:1 聚集体）。
