10.1002/chem.201903433
Chemistry - A European Journal
COMMUNICATION
With the optimized conditions in hand, we evaluated the
synthetic potential of our photochemical perfluoroalkylation
strategy (Scheme 1), by reacting differently electron-rich organic
compounds (2) with perfluoroalkyl iodides (1). In addition to the
perfluorohexyl moiety (product 3a), either a shorter or a longer
perfluorinated chain were installed in good yield to afford 3b and
3c, respectively (up to 93% yield). Interestingly, the
photochemical process is amenable to scale-up (1 mmol,
product 3a) without any erosion of the chemical yield (85% yield).
Mesitylene was also a suitable starting material, and the
resulting fluorinated adduct 3d was isolated in moderate yield
(53%). However, our attempts to react benzene under our
standard conditions resulted in poor yield (22% yield). This is
consonant with the classical homolytic aromatic substitution
(HAS) reactivity, where the absence of strongly electron-
donating groups on 2 greatly decreases the efficiency of the
reaction, because of the reduced electron density on the
Keywords: photochemistry • radical reactions • carbon
nanodots • fluoroalkylation • synthetic methods
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Acknowledgements
This work was supported by the University of Trieste. C.R.
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2014/2020
-
Friuli-Venezia
Giulia
(Regional
Code
FP1799043001) for a doctoral fellowship. This work was
performed under the Maria de Maeztu Units of Excellence
Program from the Spanish State Research Agency – Grant No.
MDM-2017-0720. We are grateful to Dr Luka Đorđević and Dr
Giulio Ragazzon for helpful discussions. We also thank Mr.
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