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Updated: Jun 22, 2026

Synthetic Methodology for Asymmetric Ferrocene Derived Bio-conjugate Systems via Solid Phase Resin-based Methodology
Published on: March 12, 2015
Electrochemistry of the inclusion complexes formed between the cucurbit[7]uril host and several cationic and neutral
1Center for Supramolecular Science and Department of Chemistry, University of Miami, Coral Gables, Florida 33124-0431, USA.
Abstract:
We have investigated the formation of inclusion complexes between the host cucurbit[7]uril (CB7) and three cationic and four neutral ferrocene-containing guests: (ferrocenylmethyl)trimethylammonium (2(+)), butyl(ferrocenylmethyl)-dimethylammonium (3(+)), (ferrocenylmethyl)heptyldimethylammonium (4(+)), hydroxymethylferrocene (5), (((methoxy)-ethoxy)ethoxy)methylferrocene (6), 1,1'-di(hydroxymethyl)ferrocene (7), and 1,1'-di((((methoxy)ethoxy)ethoxy)methyl)ferrocene (8). The formation of highly stable inclusion complexes (K > 10(7) M(-1)) was verified in all cases using NMR spectroscopic techniques. From cyclic voltammetric experiments, we observed that CB7 complexation of the cationic guests (2(+)-4(+)) leads to significant anodic shifts on the ferrocene oxidation half-wave potentials, while the measured potential shifts were smaller in the case of the neutral guests (5-8). Encapsulation of all guests resulted in a substantial decrease of the standard rate constant for heterogeneous electron transfer. However, inclusion complexation of the neutral guests led to quasi-reversible voltammetric behavior, in which the anodic peak potential is more sensitive to scan rate than the corresponding cathodic peak potential, suggesting a minor degree of structural rearrangement in the neutral inclusion complex after oxidation.
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