摘要
A palladium-catalyzed multi-acetoxylation of 1,3-disubstituted 1H-pyrazole-5-carboxylate derivatives containing multiple potential reactive sites is described. Therein, the sequence of this process has been appropriately investigated. The protocol mainly provides the di- and tri-acetoxylated products for 1,3- diarylpyrazoles. Besides, it is found that the acetoxylation of C(sp3)-H bond is prior to that of C(sp2)-H bond under structurally competitive conditions.
A palladium-catalyzed multi-acetoxylation of 1,3-disubstituted 1H-pyrazole-5-carboxylate derivatives containing multiple potential reactive sites is described. Therein, the sequence of this process has been appropriately investigated. The protocol mainly provides the di- and tri-acetoxylated products for 1,3- diarylpyrazoles. Besides, it is found that the acetoxylation of C(sp3)-H bond is prior to that of C(sp2)-H bond under structurally competitive conditions.
基金
the National Natural Science Foundation of China(Nos.21176074 and 21476074)
the Research Fund for the Doctoral Program of Higher Education of China(No.20130074110009)for financial support