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Updated: Aug 9, 2026

Synthetic Methodology for Asymmetric Ferrocene Derived Bio-conjugate Systems via Solid Phase Resin-based Methodology
Published on: March 12, 2015
Solvent- and temperature-tuned orientation of ferrocenyl azide inside beta-cyclodextrin
Peter Walla1, Vladimir B Arion, Udo H Brinker
1Institut für Organische Chemie, Universität Wien, Währinger Strasse 38, A-1090 Wien, Austria.
Abstract:
An induced circular dichroism (ICD) solution study on the orientation of ferrocenyl azide within the beta-cyclodextrin cavity is described. In DMSO, ferrocenyl azide prefers an axial inclusion, whereas in ethylene glycol and DMSO/H2O = 50/50 an equatorial alignment dominates. As shown by temperature-dependent ICD spectra, at lower temperatures ferrocenyl azide adopts preferentially an equatorial arrangement, whereas at higher temperatures an axial one is favored. Temperature and solvent effects on the co-conformation of ferrocene noncovalently bound to cyclodextrin have never been observed before.
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