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vacuum, and the residue was suspended in saturated sodium hydro-
gen carbonate solution and extracted with ethyl acetate. The ob-
tained crude product was purified by preparative HPLC (C18 re-
verse-phase column, elution with a water/MeCN gradient with
0.1% TFA). The fractions containing the product were evaporated
and lyophilized to yield a white solid.
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[14] Control experiments showed no difference in yield of the reac-
tion when racemic BINAP was used instead of (R)-BINAP. The
chiral ligand was only used as large amounts were available in
our lab.
Method B (One-Pot Procedure): The first reaction step was per-
formed as described in Method A. After heating at 80 °C for 18 h,
the iron powder and glacial acetic acid are directly added. The reac-
tion mixture was then heated at reflux for 30 min. Work-up and
product purification was conducted in the same manner as that in
method A.
Supporting Information (see footnote on the first page of this arti-
cle): General experimental methods and the characterization data
of the compounds are presented.
Acknowledgments
This work was supported by the European community by a Marie
Curie Host fellowship for the transfer of knowledge (HCTMCR).
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Received: October 19, 2010
Published Online: December 9, 2010
Eur. J. Org. Chem. 2011, 234–237
© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
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