10.1002/chem.201905535
Chemistry - A European Journal
FULL PAPER
Conclusion
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In conclusion we have synthesized three different ylide-
functionalised phosphines (L1-L3) and their corresponding
palladium allyl, cinnamyl and indenyl complexes in order to
study the impact of the ligand substitution pattern and the use of
defined precatalysts on the catalytic activity in C-N coupling
reactions. All ligands gave way to highly active catalysts that are
competent in the amination of aryl chlorides at room temperature.
While replacement of the cyclohexyl groups at phosphorus by
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a phenyl group in the ylide-
backbone (L2, joYPhos) led to considerable improvements,
particularly with respect to selectivity. A further improvement
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2
at room
temperature. The high activity of Pind2 was further confirmed by
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Conflicts of Interest
The authors have filed patent WO2019030304 covering the
YPhos ligands and precatalysts discussed, which is held by
UMICORE and products will be made commercially available
from.
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Acknowledgements
Funded by the European Research Council (Starting Grant:
YlideLigands 677749). We thank UMICORE for the donation of
chemicals. Gefördert durch die Deutsche Forschungs-
gemeinschaft (DFG) im Rahmen der Exzellenzstrategie des
Bundes und der Länder
– EXC 2033 – Projektnummer
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Keywords: Phosphines • Ligand design • structure activity
relationship • coupling reactions • Palladium
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Notes and References
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