Full Paper
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H2O (5 mL) was added to precipitate the crude product. The solid
was isolated by filtration and redissolved in CH2Cl2. This solution
was washed with water (2 × 10 mL), dried with MgSO4, and concen-
trated under reduced pressure to afford the crude product, which
was recrystallized from EtOAc/n-pentane mixtures. Details are given
in the Supporting Information.
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The reaction was then quenched with 0.1
M HCl (5 mL). The mixture
was extracted with EtOAc (3 × 10 mL), and the combined organic
phases were washed with brine (5 × 10 mL), dried with MgSO4,
and concentrated under reduced pressure. The crude products were
purified by flash column chromatography on silica (isohexane/
EtOAc, 95:5). Details are given in the Supporting Information.
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Supporting Information (see footnote on the first page of this
article): Synthetic procedures, product characterization, detailed ki-
netic and thermodynamic data, and copies of the NMR spectra of
new compounds.
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Acknowledgments
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We thank the Deutsche Forschungsgemeinschaft (SFB 749,
Project B1) for support of this work and Nathalie Hampel
for the synthesis of the reference electrophiles. A. P. thanks
Ikerbasque and the Basque Government for a postdoctoral fel-
lowship.
Keywords: Kinetics · Linear free energy relationships ·
Nucleophilicity · Malonates · Carbanions
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Received: January 29, 2016
Published Online: March 11, 2016
Eur. J. Org. Chem. 2016, 1841–1848
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