Host–guest interactions in a series of self-assembled As2L2Cl2 macrocycles
作者:Virginia M. Cangelosi、Lev N. Zakharov、Sean A. Fontenot、Melanie A. Pitt、Darren W. Johnson
DOI:10.1039/b802178c
日期:——
The reaction of AsCl3 with H2L (where L = a rigid dithiolate) results in the self-assembly of As2L2Cl2 supramolecular macrocycles. For ligands 4,4â²-bis(mercaptomethyl)biphenyl (H21), 4,4â²-bis(mercaptomethyl)-trans-stilbene (H22), and 1,4-dimethoxy-2,5-bis(mercaptomethyl)benzene (H23), the macrocyclic cavities of the resulting assemblies are large enough to host aromatic solvent molecules, as revealed by single crystal X-ray structures of the inclusion complexes. As2L2Cl2macrocycles form in solution as a mixture of diastereomers, but the diastereomers can be selectively crystallized and separated. Crystallization of syn- or anti-As232Cl2 can be controlled using hostâguest interactions by the prudent choice of crystallization solvents. anti-As232Cl2 crystallizes exclusively from chloroform and benzene, while a [(syn-As232Cl2)2·p-xylene] dimer crystallizes from p-xylene and a mixture of [(syn-As232Cl2)(anti-As232Cl2)·toluene] and [(syn-As232Cl2)2·toluene] dimers crystallize from toluene.
AsCl3 与 H2L(其中 L = 刚性二硫酸盐)的反应导致 As2L2Cl2 超分子大环的自组装。对于配体 4,4â²-双(巯基甲基)联苯 (H21)、4,4â²-双(巯基甲基)-反式二苯乙烯 (H22) 和 1,4-二甲氧基-2,5-双(巯基甲基)苯 (H23),所产生的组装体的大环空腔大到足以容纳芳香溶剂分子,这一点已被包合物的单晶 X 射线结构所揭示。As2L2Cl2macrocycles 在溶液中形成非对映异构体混合物,但非对映异构体可以选择性结晶和分离。通过谨慎选择结晶溶剂,可以利用主客体间的相互作用来控制合成或反As232Cl2的结晶。反As232Cl2只能在氯仿和苯中结晶,而[(syn-As232Cl2)2Â-对二甲苯]二聚体在对二甲苯中结晶,[(syn-As232Cl2)(anti-As232Cl2)Â-甲苯]和[(syn-As232Cl2)2Â-甲苯]二聚体的混合物在甲苯中结晶。