Graduate Student Cherry Mae Ravidas

"The Chemistry of Fluorinated Ferrocenes"

Fluorine and ferrocene are two of the sought-after research interests for organometallic chemists today. Ferrocene, after being discovered, made organometallic chemists excited to explore organometallic chemistry even more.[1] Fluorine on the other hand has attracted attention recently because of its useful properties, one of which is improving the effectivity and bio-absorption of pharmaceutically active compounds when fluorine is incorporated.[2] Combining the two was a challenging task, after a reported explosion using a dangerous fluorinating agent.[2] Nonetheless, monofluorferrocene to pentafluorinated ferrocenes now exist.[3] Some of the properties of fluorinated ferrocenes include being a better oxidizing agent than ferrocene and they easily sublime at lower temperatures which can make it easier for researchers to purify products. To further derivatize the fluorinated ferrocenes, electrophiles have been introduced to it through fluorine-directed deprotonation and the halogen “dance” reaction.[2] Besides direct fluorination on ferrocene, fluoroalkyl groups can also be added to ferrocene. Some polymers bearing fluoroalkylated ferrocenes can perform interesting chemistry such as redox-sensitive 19F MRI imaging in vitro and in vivo.[4,5]

[1]. Sünkel K., Weigand S., Hoffmann A., Blomeyer S., Reuter C.G., Vishnevskiy Y.V., and Mitzel N.W. Synthesis and Characterization of 1,2,3,4,5-Pentafluoroferrocene. Journal of the American Chemical Society 2015 137 (1), 126-129.
[2]. Tazi M., Erb W., Roisnel T., Dorcet V., Mongin F., and Low P.J. From Ferrocene to Fluorine-Containing Penta-substituted Derivatives and All Points In-Between; or, How to Increase the Available Chemical Space. Org. Biomol. Chem. 2019 17, 9352.
[3]. Erb W., Richy N., Hurvois J.P., Low P.J., and Mongin F. From Ferrocene to 1,2,3,4,5-Pentafluoroferrocene: Halogen Effect on the Properties of Metallocene. Dalton Trans., 2021 50, 16933-16938.
[4]. Švec P., Petrov OV., Lang J., Štěpnička P., Groborz O., Dunlop D., Blahut J., Kolouchová K., Loukotová L., Sedláček O., Heizer T., Tošner Z., Šlouf M., Beneš H., Hoogenboom R., and Hrubý M. Fluorinated Ferrocene Moieties as a Platform for Redox-Responsive Polymer 19F MRI Theranostics. Macromolecules 2022 55 (2), 658-671.
[5]. Kolouchova K., Cernochova Z., Groborz O., Herynek V., Koucky F., Jaksa R., Benes J., Slouf M., and Hruby M. Multiresponsive Fluorinated Polymers as a Theranostic Platform Using 19F MRI. European Polymer Journal 2022 175, 111381.