Paper
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Then, the reaction was tracked with HPLC analysis until
complete.
Acknowledgements
The authors would like to acknowledge the nancial support
from Zhejiang Provincial Key R&D Project (No. 2018C03074 &
2020C03006) and the Natural Science Foundation of Zhejiang
Province (No. LQ20B060006).
Micropacked bed continuous-ow reactor setup
The setup for the micropacked bed continuous-ow reactor
refers to the apparatus setup reported by Jensen.9 The packed
bed was laid horizontally in a water bath for temperature
control. The hydrogen gas was controlled by a hydrogen-specic
mass ow controller (DO7-19BM, max pressure 10 MPa), which
was protected by a check valve. The liquid ow was supplied
with a dual-piston HPLC pump (LC-500P constant pressure
infusion 0–15 MPa). The gas and liquid were mixed in a T-shape
mixture before the entrance of the mPBR (SS-98 max pressure
3.5 MPa). All tubes were made of stainless-steel with an outer
diameter of 1/16 inch. A manual back-pressure regulator was
placed at the outlet of the reactor to control the system pres-
sures (Fig. 5).
The catalysts were loaded into a clean HPLC column with
a diameter of 4.6 mm and a length of 150 mm, and compacted
with a high-pressure vacuum tube. The column was further
blown with nitrogen gas until the pressure of nitrogen gas
reached 0.2–0.5 MPa. The procedure was repeated several times
until the column was completely lled (approximately 4.1 g of
catalyst), and both ends were sealed with a sealing nut for use.
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Experiment process for continuous-ow reaction
The substrate 1-(4-chlorophenyl)-3-((2-nitrobenzyl)oxy)-1H-pyr-
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The packed-bed reactor was placed into a water bath of 25 ꢁC, in
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Method for product analysis
HPLC conditions. C18 chromatographic column; HPLC
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Conflicts of interest
There are no conicts to declare.
This journal is © The Royal Society of Chemistry 2020
RSC Adv., 2020, 10, 28585–28594 | 28593