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Palladium(II)-catalyzed direct intermolecular alkenylation of chromones
1Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.
Abstract:
A new efficient method for the direct alkenylation of chromones via a palladium(II)-catalyzed C-H functionalization reaction was developed. The use of pivalic acid with Cu(OAc)(3)/Ag(2)CO(3) provided superior reactivity in the cross-coupling of chromones with alkene partners. This approach represents a significant advance over the existing two-step method and afforded various 3-vinylchromone derivatives, which are privileged structures in many biologically active compounds and versatile synthetic building blocks.
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