Efficient synthesis of pyrazolopyridines containing a chromane backbone through domino reaction

• Razieh Navari,
• Saeed Balalaie,
• Saber Mehrparvar,
• Fatemeh Darvish,
• Frank Rominger,
• Fatima Hamdan and
• Sattar Mirzaie

Beilstein J. Org. Chem. 2019, 15, 874–880, doi:10.3762/bjoc.15.85

• base led to a fused chromanyl-cyanopyridine. High selectivity, high atom economy, and good to high yields in addition to mild reaction conditions are the advantages of this approach. Keywords: chromane; domino reaction; fused heterocyclic skeletons; pyrazolopyridines; Introduction The synthesis of

• construct fused heterocyclic skeletons [37][38][39][40], we describe the synthesis of pyrazolopyridines 4a–m containing a chromone moiety (Scheme 1). The synthetic approach was based on a domino reaction of (arylhydrazono)methyl-4H-chromen-4-one 1a–g, primary amines 2a–c, and malononitrile (3) in the

• fused heterocyclic backbones with high selectivity. Conclusion In conclusion, we have successfully established an efficient route toward the synthesis of a diverse array of fused heterocyclic skeletons through a domino reaction. We showed an interesting behavior of the base for the cyclization reaction