Crystalline Self-Assembly of a Bowl-Like Cyclotriguaiacylene Derivative with Alcohol/Phenols by Hydrogen Bonding and C−H···π Interactions: The Self-Inclusion Extended Organic Frameworks
journal contributionposted on 06.01.2010, 00:00 by Yan-Yan Shi, Junliang Sun, Zhi-Tang Huang, Qi-Yu Zheng
Bowl-like tris-[(N-methyl-2-imidazolyl)methoxy]cyclotriguaiacylene (TMIM-CTG) (1) was synthesized and cocrystallized with ethanol, resorcinol, and phloroglucinol to afford three molecular complexes (TMIM-CTG)·(ethanol)3 (2), (TMIM-CTG)·(resorcinol)·(CH3CN)2 (3), and (TMIM-CTG)·(phloroglucinol)·(CH3CN)2 (4), whose structures have been determined by X-ray single crystal analysis. Except for the hydrogen bonds between imidazole of 1 and the hydroxyl group of alcohol/phenols (O−H···N), all crystals contain self-inclusion motifs with cooperative C−H···π interactions which can be considered as the secondary way to extend the primary hydrogen-bonded networks to the frameworks with higher levels. In complex 2, two adjacent TMIM-CTGs form a self-clasping dimer by an edge-to-face C−H···π interaction between the imidazole ring and the benzene ring of CTG, which is further extended to a one-dimensional chain by the π−π interactions between adjacent imidazole rings. The ethanol molecules interact with TMIM-CTGs by hydrogen bonding and fill channels within these chains. In complex 3, the self-assembly of TMIG-CTG and resorcinol molecules by hydrogen bonding affords the zigzag chain, which is then extended to the (4,4) sheet by the self-inclusion between TMIG-CTGs. Complex 4 contains a two-dimensional 4.82 hydrogen-bonding network between TMIG-CTG and phloroglucinol molecules, and the self-inclusion of TMIG-CTGs extends it to a novel three-dimensional supramolecular framework. The acetonitrile molecules in two latter crystals are included within the extended organic framework.