Tetrathiafulvalene‐Based Macrocycles Formed by Radical Cation Dimerization: The Role of Intramolecular Hydrogen Bonding and Solvent |
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| Authors: | Wei‐Kun Wang Yuan‐Yuan Chen Dr. Hui Wang Prof. Dr. Dan‐Wei Zhang Prof. Dr. Yi Liu Prof. Dr. Zhan‐Ting Li |
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| Affiliation: | 1. Department of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433 (China), Fax: (+86)?21‐6564‐1740;2. The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (USA) |
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| Abstract: | Compounds 1 a and 1 b were prepared by appending two tetrathiafulvalene (TTF) units to an aromatic amide segment that is driven by six or two intramolecular N? H???O hydrogen bonds to adopt a folded conformation. UV/Vis absorption experiments revealed that if the TTF units were oxidized to TTF.+ radical cations, the two compounds could form a stable single molecular noncovalent macrocycle in less polar dichloromethane or dichloroethane or a bimolecular noncovalent macrocycle in a binary mixture of dichloromethane with a more polar solvent owing to remarkably enhanced dimerization of the TTF.+ units. The stability of the (TTF.+)2 dimer was evaluated through UV/Vis absorption, electron paramagnetic resonance, and cyclic voltammetry experiments and also by comparing the results with those of control compound 2 . The results showed that introduction of the intramolecular hydrogen bonds played a crucial role in promoting the stability of the (TTF.+)2 dimer and thus the noncovalent macrocyclization of the two backbones in both uni‐ and bimolecular manners. |
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| Keywords: | foldamers hydrogen bonds macrocyclization radical cation dimerization solvent effects |
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