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Scheme 4. Proposed catalytic cycle.
a range of aryl allene derivatives, affording vinyl silanes with
excellent efficiency. The use of a seven-membered NHC ligand
was crucial to obtain high levels of regiocontrol. Trapping of
the catalytically generated allylcopper intermediates with alde-
hydes furnishes homoallylic alcohols with excellent regiocon-
trol and diastereoselectivity. Further studies to extend and
apply this new method are underway in our laboratory.
Acknowledgement
We thank the University of Manchester (J.P.R.) and Leverhulme
Trust (Leverhulme Research Fellowship to D.J.P). We also thank
Gareth Smith for help with Mass Spectrometry.
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Ito, Organometallics 2000, 19, 4647.
Keywords: allenes · copper · homogeneous catalysis · N-
heterocyclic carbenes · silylation
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of allenoates was reported: a) Y.-H. Xu, L.-H. Wu, J. Wang, T.-P. Loh,
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Received: July 10, 2014
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