G Model
CCLET-6298; No. of Pages 5
L. Huang, J. Xu, L. He et al.
Chinese Chemical Letters xxx (xxxx) xxx–xxx
the corresponding products in moderate to good yields. Control
experiments revealed that a Mannich-type reaction and oxidative
process were involved in the transformation.
Declaration of competing interest
The authors declare that they have no conflict of interest.
Acknowledgments
We thank the Natural Science Foundation of Zhejiang Province
(No. LY21B060009) and the National Natural Science Foundation of
China (No. 21871071) for financial support.
Appendix A. Supplementary data
Supplementarymaterialrelatedtothisarticlecanbefound, inthe
References
Scheme 6. Plausible mechanism.
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In conclusion, this study described a novel strategy for the
olefination of quinoxalin-2(1H)-ones with methyl ketones. Various
substrates were compatible under standard condition, providing
4