ARTICLES
reactor at a flow rate of 1 ml h21. For the rearrangement reaction, 0.05 mmol of
PhICl2, 0.5 mmol of PhMe6, 0.5 mmol of enyne 4 and 0.5 mmol of propargyl
pivalate 1 were dissolved in 30 ml of toluene. This solution was pumped through the
reactor at flow rates between 0.01 ml h21 and 5 ml h21. The conversion and product
yield were monitored by gas chromatography (GC, gas chromatograph HP5890II
equipped with a 30 m HP-5 capillary column) and by 1H NMR spectroscopy.
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Elemental analysis by ICP-MS. After the reaction period was over, the reaction
mixture was filtered through a glass microfibre filter (Whatman GF-H), and both the
supernatant and solid catalysts were collected. The Au catalyst was mixed with aqua
regia (concentrated HCl:concentrated HNO3 ¼ 3:1, 1 ml) solution for 10 hours.
After the Au-containing species had dissolved, the residual white solid (SBA-15) was
filtered and the acidic solution mixed with 6 ml of H2O and analysed by ICP-MS. To
analyse the filtrate by ICP-MS, toluene was evaporated under reduced pressure and
the remaining solids were dissolved in 1 ml aqua regia and 6 ml H2O. This solution
was also analysed by ICP-MS.
Received 25 January 2012; accepted 17 August 2012;
published online 30 September 2012
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Acknowledgements
We acknowledge support from the Director, Office of Science, Office of Basic Energy
Sciences, Division of Chemical Sciences, Geological and Biosciences of the US Department
of Energy (DOE) under contract DE-AC02-05CH11231. Nanoparticle TEM imaging was
performed by S. Alayoglu at the Molecular Foundry Imaging Facility, Lawrence Berkeley
National Laboratory, which is supported by the Office of Science, Office of Basic Energy
Sciences of the US DOE under contract DE-AC02-05CH11231.
Author contributions
E.G. and J.H.L. performed the experiments and synthesized materials, substrates and
catalysts. F.D.T. and G.A.S. supervised the research. All authors contributed to the
conception of the experiments, discussed the results and commented on the manuscript.
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tetramethyldisiloxane to alkynes catalyzed by supported gold nanoparticles.
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Additional information
Supplementary information and chemical compound information are available in the
18. Shakeri, M., Tai, C. W., Go¨thelid, E., Oscarsson, S. & Ba¨ckvall, J. E. Small Pd
nanoparticles supported in large pores of mesocellular foam: an excellent catalyst Competing financial interests
for racemization of amines. Chem. Eur. J. 17, 13269–13273 (2011).
The authors declare no competing financial interests.
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