Journal of the American Chemical Society
COMMUNICATION
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absorption and C MAS NMR spectra. This material is available
free of charge via the Internet at http://pubs.acs.org.
’
AUTHOR INFORMATION
Corresponding Author
nancy.goroff@stonybrook.edu
’
ACKNOWLEDGMENT
We thank the National Science Foundation (CHE-0911540,
CHE-0446749, and DMR-0804737) for support of this research.
We thank Prof. Daniel P. Raleigh and Dr. Fanling Meng for help
in UVÀvis absorption spectroscopy and Prof. Joseph W. Lauher
for help in optical microscopy. We also thank Dr. Bing Luo, Kai-
yuan Chen, and Dr. Feng Zuo of the University of Minnesota for
help in XPS, TGA, and DSC.
Figure 4. AC frequency-dependent conductivity of bulk samples of
PIDA and base-treated PIDA at a fixed amplitude of 1.0 V.
À1
peaks centered at 1360 and 1580 cm25 (Figure 3), similar to
graphitic carbon and carbon nanofibers. The breadth of the peaks
suggests significant disorder in the structure of base-treated samples,
but may also be attributed to the amorphous surface of the materials
after the reaction or incomplete carbonization of the PIDA.
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magnetically inactive salt. This phenomenon indicates the
27À29
generation of eddy currents,
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13
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consistent with the observations from C MAS NMR.
In summary, we have observed that Lewis bases can react with
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base-induced dehalogenation is a general reaction of trans-
diiodoalkenes and pyrrolidine. With at least ∼60% of the original
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reaction between PIDA and Lewis bases presents a novel chemical
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cause explosion in some cases. For more information, see Safety
Statement in Supporting Information.
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ASSOCIATED CONTENT
S
Supporting Information. Experimental details for reac-
b
tions of PIDA and model systems, and additional UVÀvis
(23) See SI for detailed calculation based on elemental analysis.
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