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Green Chemistry
the mixture was stirred under reflux conditions at 110 °C for sion systems was calculated briefly with diffusion distant
12 h. After cooling down to room temperature, the solid divided by time.
materials were filtered, washed with methanol and toluene,
and subsequently dried under vacuum at room temperature.
The materials were denoted as DMSN-C18N-X, in which X Conflicts of interest
refers to the mmol amount of C18N per gram of DMSN used
There are no conflicts to declare.
during the grafting process. For example, DMSN-C18N-0.8 rep-
resents the material synthesized with 1.0 g of DMSN and
0.8 mmol of C18N.
Acknowledgements
Construction of Pickering emulsion system for catalyzing the
hydroformylation reaction
This work was supported by the National Key Research and
Development Program of China (No. 2017YFB0702800), the
NSFC (No. 21232008, 21621063) and the Strategic Priority
Research Program of the Chinese Academy of Sciences Grant
(No. XDB17020200).
IL-in-oil Pickering catalytic emulsion system: a mixture of
Rh(acac)(CO)2 (11.67 mg, 4.5 mmol) and desired amount of
phosphine ligand were dissolved in 2 mL of degassed methanol
for 0.5 h. After addition of 10 ml of [BMIM][BF4], the solution
was stirred under N2 atmosphere overnight. The catalyst solution
was obtained after removing methanol under vacuum at 40 °C.
DMSN-C18N-X, 1-dodecene (1 mL) and tetradecane (0.3 mL
as internal standard) were added to a glass vial. After ultra-
sonication for 1 min, the catalyst solution prepared above
(1 mL) was added. Subsequently the mixture was vigorously
shaken for about 15 min to form the IL-in-oil emulsion. Then
the emulsion was transferred to an autoclave (25 mL). Before
the reaction, the autoclave was purged three times with CO/H2
(molar ratio = 1 : 1). Then, the pressure was raised to 20 bar
and the autoclave was stirred in an oil bath at 110 °C for a
desired time interval. After the autoclave was cooled down to
room temperature, the gas was carefully released. The organic
layer was separated by centrifugation, diluted with toluene and
analyzed by gas chromatography on a HP-5 capillary column
(30 m × 0.32 mm × 0.25 mm).
For the catalyst recycling, the IL phase containing catalyst
and solid materials were obtained after centrifugation and
washed with toluene 3 times. Then the substrate and internal
standard were added for the next catalytic reaction.
Water-in-oil Pickering catalytic emulsion system: the con-
struction of the water-in-oil Pickering emulsion system is
similar to that of the IL-in-oil Pickering emulsion system with
the exception that water is used instead of [BMIM][BF4].
The IL-oil biphasic catalytic reaction system was prepared
in a method similar to that of the IL-in-oil Pickering emulsion
system with the exception that no DMSN was used.
Notes and references
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General procedure for preparing continuous flow Pickering
emulsion31
A glass column with a sand filter and a valve at the bottom was
chosen as the column reactor. The inner diameter of the 16 Y. Zhao, X. Zhang, J. Sanjeevi and Q. H. Yang, J. Catal.,
column is 1.05 cm. The desired volume of the emulsion was 2016, 334, 52.
prepared as mentioned before. After one piece of membrane 17 H. Q. Yang, L. M. Fu, L. J. Wei, J. F. Liang and B. P. Binks,
(oil-permeable but water-impermeable) was spread out on the J. Am. Chem. Soc., 2015, 137, 1362.
sand filter, 3 g of silica was added. The prepared Pickering 18 J. P. Huang and H. Q. Yang, Chem. Commun., 2015, 51,
emulsion was poured carefully into this column; after that, 7333.
1-dodecene dyed with Sudan I was added on top of the emul- 19 L. Kollar and J. Dupont, Ionic Liquids (ILs) in Organometallic
sion. The diffusion rate of dyed 1-dodecene in different emul-
Catalysis, Verlag, Heidelberg, 2015.
Green Chem.
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