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RESEARCH PRODUCT
Achieving Strong Positive Cooperativity through Activating Weak Non-Covalent Interactions
Yan-long MaYan-long MaHua KeKari RissanenWei JiangArto Valkonensubject
chemistry.chemical_classification010405 organic chemistryChemistryHydrogen bondStereochemistrycooperativitySupramolecular chemistrymolecular tubesCooperativityGeneral ChemistryDABCO010402 general chemistryhydorogenchemistry01 natural sciencesCatalysis0104 chemical scienceschemistry.chemical_compoundionsMoleculeNon-covalent interactionsmoleculesHost–guest chemistryTernary complexta116description
Positive cooperativity achieved through activating weak non-covalent interactions is common in biological assemblies but is rarely observed in synthetic complexes. Two new molecular tubes have been synthesized and the syn isomer binds DABCO-based organic cations with high orientational selectivity. Surprisingly, the ternary complex with two hosts and one guest shows a high cooperativity factor (α=580), which is the highest reported for synthetic systems without involving ion-pairing interactions. The X-ray single-crystal structure revealed that the strong positive cooperativity likely originates from eight C-H⋅⋅⋅O hydrogen bonds between the two head-to-head-arranged syn tube molecules. These relatively weak hydrogen bonds were not observed in the free hosts and only emerged in the complex. Furthermore, this complex was used as a basic motif to construct a robust [2+2] cyclic assembly, thus demonstrating its potential in molecular self-assembly.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2018-01-15 | Angewandte Chemie International Edition |