Synthetic approach to flavanones and flavones via ligand-free palladium(ii)-catalyzed conjugate addition of arylboronic acids to chromonesElectronic supplementary information (ESI) available: 1H and 13C NMR spectra. See DOI: 10.1039/c2ob26061a

• Main Authors: Kim, Donghee, Ham, Kyungrok, Hong, Sungwoo
• Format: Article
• Language: English
• ISSN: 1477-0520; 1477-0539
• DOI: 10.1039/c2ob26061a

The remarkable catalytic effects of Fe(OTf) 3 in the context of the Pd( ii )-catalyzed conjugate addition of arylboronic acids to chromones were observed to yield a variety of flavanones under mild conditions. The addition of catalytic amounts of DDQ and KNO 2 to the reactions exclusively yielded flavone analogs. The reaction scope for the transformation was fairly broad, affording good yields of a wide range of flavanones and flavones, which are privileged structures in many biologically active compounds. The remarkable catalytic effects of Fe(OTf) 3 in the context of the Pd( ii )-catalyzed conjugate addition of arylboronic acids to chromones were observed to yield a variety of flavanones under mild conditions. The addition of catalytic amounts of DDQ and KNO 2 to the reactions exclusively yielded flavone analogs.