Inorganic Chemistry
Communication
ASSOCIATED CONTENT
Supporting Information
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*
S
Experimental details, analytical performance criteria (Table S1),
chromatograms of DMF, 5:1 DMF/TEOA, and an anion
mixture (Figure S1), formate determination in DMF in the
absence of base (Figure S2), effect of time on formate
production in 5:1 DMF/TEOA solutions (Figure S3), effect of
the water concentration on the formate levels in 5:1 DMF/TEA
solutions (Figure S4), effect of time on formate production in
5
:1 DMF/TEA solutions (Figure S5), qualitative identification
1
3
of formate in 5:1 DMF/TEA via spiking (Figure S6), C NMR
of a 5:1 DMF/TEA mixture containing 80 vol % H O (Figure
2
S7), IR spectrum of a 5:1 DMF/TEA mixture containing 80 vol
1
3
%
H O (Figure S8), C NMR of DMF in D O (Figure S9),
2
2
1
3
C NMR (600 MHz) of 5:1 DMF/TEA in D O (Figure S10),
2
Figure 4. Effect of time and the water concentration (50−90% v/v) on
and mechanism for the hydrolysis of DMF (Figure S11). This
the formate concentration in a 5:1 DMF/TEA solution.
%
H O after 2 h, whereas when the relatively weak organic base
2
was replaced with the stronger base TEA, formate production
AUTHOR INFORMATION
7005503.
−3
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increased to 3.61 × 10 M.
13
C NMR was again used to confirm the presence of formate
*
in aqueous DMF/TEA mixtures. Figure S7 in the SI shows
characteristic peaks for formate (170.6 ppm) and dimethyl-
amine (35.5 ppm) as well as DMF (164.8, 36.9, and 31.4 ppm)
1
Notes
The authors declare no competing financial interest.
1
3
and TEA (46.0 and 9.1 ppm). The C NMR spectrum in D O
2
of a sample of 5:1 DMF/TEA (in the absence of added H O)
2
ACKNOWLEDGMENTS
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was obtained at various times (0−72 h); see Figure S10 in the
SI. Peaks for DMF, TEA, and the degradation products of DMF
hydrolysis, both formate and dimethylamine, were observed.
Fourier transform infrared (FTIR) spectroscopy also confirmed
the presence of formate, as illustrated in Figure S8 in the SI.
We acknowledge the Environmental Protection Agency (EPA
Grant 2008-ET-MS-3-S2) and Science Foundation Ireland (SFI
Grant 08/SRC/B1412) for supporting this work.
REFERENCES
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Overlaid FTIR spectra of DMF/H O, formate, and DMF/
2
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2
−1
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−1
1
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2
This study shows that caution should be exercised when
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(
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2
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dx.doi.org/10.1021/ic202121s | Inorg. Chem. 2012, 51, 1977−1979