ol2c02476_si_001.pdf (11.34 MB)
Palladium-Catalyzed Chemo- and Regiocontrolled Tandem Cyclization/Cross-Coupling of 2‑Benzyl-3-alkynyl Chromones with Aryl Iodides for the Synthesis of 4H‑Furo[3,2‑c]chromenes and Xanthones
journal contributionposted on 2022-08-09, 14:20 authored by Yi-En Liang, Chih-Yu Kan, Balaji D. Barve, Yen-An Chen, Wen-Tai Li
A novel Pd-catalyzed chemo- and regiocontrolled tandem cyclization/cross-coupling reaction of 3-alkynyl chromone with aryl iodide was developed for the synthesis of 4H-furo[3,2-c]chromenes and xanthones. The difunctionalization of alkynes through O-attack/5-exo-dig and C-attack/6-endo-dig cyclization was reported by this rare approach, which was selectively controlled by the addition of KF or a bidentate phosphine ligand. A one-pot tandem process was demonstrated directly from γ-alkynyl-1,3-diketone for this method.