Communication
ChemComm
multiple mechanisms using theoretical calculations. As demon-
strated, the important roles of the DAP primer in the photo-
redox reaction of o-PD exemplify the multi-electron transfer and
energy transfer kinetics of DSP. This study has demonstrated
the potential of AMS for studying the mechanism of hetero-
geneous catalytic reactions. More efforts on both technique
improvements and reaction examinations are encouraged to
extend the development of photocatalysis and the applicability
of ambient mass spectrometry.
N. Na, J. Sun, H. Lu, Y. Zhang Y. Wang and Y. Zhao gratefully
acknowledge the financial support provided by the National
Key Research and Development Program of China (No.
2019YFC1805600) and the National Natural Science Foundation
of China (NNSFC 21874012). J. Ouyang is grateful for the
financial support provided by NNSFC (21974010).
Fig. 5 Possible mechanism of self-sensitized DSP via photoelectron
transfer between the excited state DAP* and TiO
or intermediates during the reaction.
2
. 1–11: important species
Conflicts of interest
There are no conflicts to declare.
the presence of H O , intermediate 5 can be oxidized into
2
2
intermediate 6 (which produces an ion of m/z 213 upon ESI),
which can be cyclized into intermediate 7. Finally, the product
of DAP can be generated by the oxidation of intermediate 7.
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À1
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À1
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mechanism shown in Fig. 5.
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Chem. Commun., 2021, 57, 3921–3924
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