One‐Step Synthesis of 2‐Amino‐3‐cyano‐4‐ aryl‐1,4,5,6‐tetrahydropyrano[3,2‐c]quinolin‐5‐one Derivatives Using KF–Al₂O₃ as Catalyst

Abstract

A series of 2‐amino‐3‐cyano‐4‐aryl‐1,4,5,6‐tetrahydropyrano[3,2‐c] quinolin‐5‐one derivatives were synthesized by the reaction of arylaldehyde, malononitrile, and 4‐hydroxyquinolin‐2‐one in ethyl alcohol at 80°C catalyzed by KF–Al₂O₃. The structure of the product was confirmed by x‐ray analysis.

Keywords:

• Pyrano[3,2‐c] quinolin‐5‐one
• 4‐Hydroxyquinolin‐2‐one
• KF–Al₂O₃
• Synthesis

Acknowledgment

We are grateful to the Foundation of the “Surpassing Project” of Jiangsu Province and Natural Science Foundation of the Education Committee of Jiangsu Province for financial support.

Notes

^aX‐ray crystallography for 4f: empirical formula C₂₂H₂₁N₅O₆, F _W = 451.44, T = 296(2) K, Triclinic, space group P‐1, a = 9.109(2) Å, b = 11.340(2) Å, c = 12.458(2) Å, α = 70.02(1)°, β = 69.36(1)°, γ = 67.32(1)°, V = 1081.4(4) Å³, Z = 2, Dc = 1.386 Mg/m³, λ(MoKα) = 0.71073 Å, μ = 0.103 mm⁻¹, F(0 0 0) = 472. 1.79° < θ < 25.24°, R = 0.0452, wR = 0.1106. S = 0.875, Largest diff. Peak and hole: 0.205 and −0.198 e Å⁻³.