Direct C-H Alkenylation of Functionalized Pyrazoles
Su Jin Han1, Hyun Tae Kim1, Jung Min Joo1
1Department of Chemistry and Chemistry Institute of Functional Materials, Pusan National University , Busan 46241, Republic of Korea.
Abstract:
We have developed inter- and intramolecular C-H alkenylation reactions of pyrazoles. The catalyst, derived from Pd(OAc)2 and pyridine, enabled the oxidative alkenylation of pyrazoles containing a variety of functional groups at the C4 position. Activated alkenes, including acrylate, acrylamide, and styrene derivatives, and enamides could be installed in this process. The sequential C-H alkenylation and cyclization reactions gave rise to fused bicyclic pyrazoles, providing a new strategy to annulate readily available pyrazole compounds.
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