Host-guest interactions in a series of self-assembled As(2)L(2)Cl(2) macrocycles.
June 28th, 2008 | by admin |Host-guest interactions in a series of self-assembled As(2)L(2)Cl(2) macrocycles.
The reaction of AsCl(3) with H(2)L (where L = a rigid dithiolate) results in the self-assembly of As(2)L(2)Cl(2) supramolecular macrocycles. For ligands 4,4\’-bis(mercaptomethyl)biphenyl (H(2)), 4,4\’-bis(mercaptomethyl)-trans-stilbene (H(2)), and 1,4-dimethoxy-2,5-bis(mercaptomethyl)benzene (H(2)), 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. As(2)L(2)Cl(2) macrocycles form in solution as a mixture of diastereomers, but the diastereomers can be selectively crystallized and separated. Crystallization of syn- or anti-As(2)(2)Cl(2) can be controlled using host-guest interactions by the prudent choice of crystallization solvents. anti-As(2)(2)Cl(2) crystallizes exclusively from chloroform and benzene, while a [(syn-As(2)(2)Cl(2))(2).p-xylene] dimer crystallizes from p-xylene and a mixture of [(syn-As(2)(2)Cl(2))(anti-As(2)(2)Cl(2)).toluene] and [(syn-As(2)(2)Cl(2))(2).toluene] dimers crystallize from toluene.
Cangelosi VM, Zakharov LN, Fontenot SA, Pitt MA, Johnson DW.
Department of Chemistry and Materials Science Institute, University of Oregon, Oregon Nanoscience and Microtechnologies Institute (ONAMI), Eugene, OR 97403-1253, USA. dwj@uoregon.edu.