Palladium-Mediated Bis-Arylation of Inactivated and Activated Arenes

Abstract

A simple synthetic protocol has been developed for the bis-arylation of unactivated and activated arenes by the implementation of a palladium-catalyzed intramolecular cyclization strategy. The activated arenes give either linearly fused or angularly fused bis-cyclized product depending upon the substitutent present on the nitrogen atom, whereas inactivated arenes give only linearly fused product. The reaction has been carried out in two steps under ligand-free conditions.

Keywords:

• Biaryl coupling
• bis-cyclization
• palladium acetate
• pyridonaphthyridinedione
• pyridoquinolinedione

ACKNOWLEDGMENT

We thank the Council of Scientific and Industrial Research (CSIR) (New Delhi) and the Department of Science and Technology (New Delhi) for financial assistance. Two of us (S. C. and N. D.) are grateful to the CSIR and the University Grants Commission, respectively, for fellowships.

Notes

^a 10 mol % of catalyst was used in all cases.

^b The reaction was carried out at 110 °C in DMF and at 85 °C in MeCN.

^c NR, no reaction.