Hahn Raiko, Bohle Fabian, Fang Wenwen, Walther Andreas, Grimme Stefan, Esser Birgit
Institute for Organic Chemistry , University of Freiburg , Albertstraße 21 , 79104 Freiburg , Germany.
Mulliken Center for Theoretical Chemistry , University of Bonn , Beringstraße 4 , 53115 Bonn , Germany.
J Am Chem Soc. 2018 Dec 26;140(51):17932-17944. doi: 10.1021/jacs.8b08823. Epub 2018 Dec 11.
Aromatic donor-acceptor interactions are of high importance in supramolecular chemistry, materials science and biology. Compared to other noncovalent interactions, such as hydrogen bonding, the binding is often weak. Here we show that strong donor-acceptor interactions between planar aromatics with binding free energies down to -10.1 kcal mol and association constants of up to 2.34 × 10 L mol for 1:1 complexes can be realized using cyclic trinuclear complexes of gold(I) with pyridinate, imidazolate, or carbeniate ligands. Data were obtained through NMR and UV/vis absorption spectroscopic studies and supported by quantum chemical calculations for a variety of acceptors. By using a specifically designed bridged naphthalene diimide-based acceptor with only one binding site, we furthermore show that a 1:2 (donor:acceptor) binding model is best suited to quantify the donor and acceptor/complex equilibrium. Scanning electron microscopy on selected donor-acceptor pairs shows crystalline supramolecular assemblies. We anticipate this study to be relevant for the future design of supramolecular systems and chemical sensors and the determination of binding energies between planar donors and acceptors.
芳香供体-受体相互作用在超分子化学、材料科学和生物学中具有高度重要性。与其他非共价相互作用（如氢键）相比，这种结合通常较弱。在此我们表明，使用金（I）与吡啶酸酯、咪唑酸酯或碳烯酸酯配体形成的环状三核配合物，可实现平面芳烃之间具有低至-10.1 kcal/mol的结合自由能以及高达2.34×10⁶ L/mol的缔合常数（对于1:1配合物）的强供体-受体相互作用。数据通过核磁共振（NMR）和紫外/可见吸收光谱研究获得，并得到了多种受体的量子化学计算的支持。通过使用仅具有一个结合位点的经过特殊设计的桥连萘二亚胺基受体，我们进一步表明1:2（供体:受体）结合模型最适合于量化供体与受体/配合物的平衡。对选定的供体-受体对进行的扫描电子显微镜观察显示出晶体超分子组装体。我们预计这项研究对于超分子系统和化学传感器的未来设计以及平面供体与受体之间结合能的测定具有重要意义。
