Berger Gilles, Soubhye Jalal, van der Lee Arie, Vande Velde Christophe, Wintjens René, Dubois Philippe, Clément Sébastien, Meyer Franck
Chimie Pharmaceutique Organique, Faculty of Pharmacy, Université Libre de Bruxelles (ULB), Boulevard du Triomphe, 1050 Bruxelles (Belgium).
Institut Européen des Membranes, CNRS-UMR 5635, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier Cedex 05 (France).
Chempluschem. 2014 Apr;79(4):552-558. doi: 10.1002/cplu.201400005. Epub 2014 Feb 5.
The supramolecular organization of modified thiophenes resulting from N⋅⋅⋅I halogen bonding (XB) has been studied. X-ray diffraction analyses of two polymorphs of the same supramolecular complex showed an arrangement controlled by halogen-bonded pyridyl and tetrafluoroiodobenzene rings, one case with and the other without the presence of two different lone pair (lp)⋅⋅⋅π interactions, namely O⋅⋅⋅pyridyl and I⋅⋅⋅tetrafluoroiodobenzene contacts. To shed light on the interplay between these interactions, quantum mechanical calculations were performed at the ωB97X-D/6-31+G(d,p) level on both systems in the gas phase. The longer N⋅⋅⋅I distance observed in the crystal structure without lp⋅⋅⋅π interactions was also corroborated by dispersion-corrected DFT. These results represent the first case in which a synergy between lp⋅⋅⋅π interactions and XB is observed experimentally and confirmed by calculations.
对由N⋅⋅⋅I卤素键（XB）形成的修饰噻吩的超分子结构进行了研究。对同一超分子配合物的两种多晶型物进行的X射线衍射分析表明，其排列受卤素键合的吡啶基环和四氟碘苯环控制，一种情况存在两种不同的孤对（lp）⋅⋅⋅π相互作用，即O⋅⋅⋅吡啶基和I⋅⋅⋅四氟碘苯接触，另一种情况则不存在。为了阐明这些相互作用之间的相互影响，在ωB97X-D/6-31+G(d,p)水平上对气相中的两个体系进行了量子力学计算。在没有lp⋅⋅⋅π相互作用的晶体结构中观察到的较长的N⋅⋅⋅I距离也得到了色散校正DFT的证实。这些结果代表了首次通过实验观察到并经计算证实lp⋅⋅⋅π相互作用与XB之间协同作用的情况。
