CHUMKAEO ET AL.
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XRD diffractograms suggested that the structure and
composition of the recovered catalyst were retained
under the catalytic condition of the Ullmann
homocoupling reaction as shown in Figure 17S. However,
Pd ions or nanopaticles were not observed in XRD
diffractograms (in both fresh and recovered catalysts).
Therefore, additional characterization techniques were
investigated to complete the analysis. To confirm the
presence of Pd, the chemical composition of Pd derived
from the recovered PFL1 catalyst was successfully con-
firmed by high‐resolution XPS technique (Figure 18S). It
was obvious that the presence of palladium was observed
in the recovered PFL1 catalyst. There was no significant
difference of the chemical composition of Pd between
fresh and recovered catalysts in XPS spectra. Moreover,
the presence of palladium metal in the recovered PFL1
catalyst was further confirmed by EDX spectrum (Figure
19S). Also, the content of Pd of the recovered PFL1 cata-
lyst was further investigated and confirmed by ICP‐OES
analysis. For quantitative analysis, the content of palla-
dium in the fresh and recovered catalysts showed compa-
rable results (Table 5S). This analysis also provided the
confirmation that the prepared catalysts showed good
catalytic activities without the leaching of Pd ions into
the reaction media.
design and synthesize catalyst for cascade acylation
reaction of chloroarenes with primary alcohol. Further
investigation for tuning the selectivity of acylation
reaction is underway.
ACKNOWLEDGMENTS
The authors thank the Thailand Research Fund
(RSA6080010) and the Royal Golden Jubilee Scholarship
to PC [PHD/01242556] for financial supports and Prof.
Jan J. Weigand for generously donating us ethanol‐d6.
ORCID
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