Abstract
(Chemical Equation Presented) The encapsulation of cobaltocenium (Cob +) inside hexameric molecular capsules of two different resorcinarenes was investigated in dichloromethane solution. Both 1H NMR spectroscopic and voltammetric experiments clearly reveal that Cob + experiences encapsulation. Diffusion coefficient measurements obtained from PGSE NMR experiments indicate that the molecular capsules exist in dichloromethane solution in the absence of any cations. Bound and free Cob + ions undergo slow exchange on the NMR time scale, but the bound Cob+ ions rotate and/or tumble freely inside the molecular capsules. Under experimental conditions suitable for voltammetry the encapsulation of Cob+ depends on the nature of the supporting electrolyte. Tetraalkylammonium hexafluorophosphate, tetrafluoroborate, and perchlorate supporting electrolytes prevent the encapsulation of Cob+, while tetraalkylammonium chloride and bromide salts allow it. The nature of the tetraalkylammonium cation plays a smaller role in the encapsulation. Finally, the structure of the resorcinarene also factors into the overall stability of the molecular assembly.
Original language | English (US) |
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Pages (from-to) | 1558-1564 |
Number of pages | 7 |
Journal | Journal of Organic Chemistry |
Volume | 70 |
Issue number | 5 |
DOIs | |
State | Published - Mar 4 2005 |
ASJC Scopus subject areas
- Organic Chemistry