Journal of Inorganic and General Chemistry
SHORT COMMUNICATION
Zeitschrift für anorganische und allgemeine Chemie
Supporting Information (see footnote on the first page of this article):
Experimental Section, Tables, Formulas, NMR spectrum of 1e, BDEs.
matic), introducing the first reported rare earth metal catalyzed
C–F bond activation. LiAlH4 was used as hydride source. The
precatalyst with the highest conversion for hexafluoropropene
(6) is precatalyst 1e, for the other substrates the precatalysts
with larger ionic radii show higher reactivity. For 6 complete
Acknowledgements
conversion to the hydrodefluorinated products and TONs up to Support from the Deutsche Forschungsgemeinschaft (DFG) is grate-
fully acknowledged.
155 could be observed. HDF reactions of chlorotrifluoroethene
(13) demonstrate that the C–F bond activation is favored over
the C–Cl bond activation with a relatively high chemoselectiv-
ity, although regioselectvity and conversions were low.
Applying catalysts with different substitution patterns on the
Cp ligand and variation of the central metal atom influences
their steric and electronic properties and can lead to a lower
or even higher reactivity and selectivity. Further studies to op-
timize the rare earth metal-catalyzed C–F bond activation and
to clarify the mechanism are currently in progress.
Keywords: Lanthanides; Catalysis; Hydrodefluorination;
Lithium aluminum hydride
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Experimental Section
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The conversion of the substrates was determined by NMR spectra by
integration of product resonances vs. the internal standard (fluorobenz-
ene). The products were identified by 19F NMR spectroscopy
([D6]benzene), using available literature data for 7a–7b,[26] 7c,[27] 7d–
7e,[28] 8a–8c,[29] 8d,[27] 9b,[30] 10a–10c,[31] 12a–12c,[32] 14a–14d,[33]
16a,[34] 16b,[35] or by comparison with an authentic sample (11, 9a,
12d).
CAUTION: Mixtures of fluorocarbons and alanes or LiAlH4 are ther-
modynamically unstable and can lead to explosions. DIBAL is pyro-
phoric and the LiAlH4 residue, if it still contains any ether, is also
extremely pyrophoric.
Z. Anorg. Allg. Chem. 0000, 0–0
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