A Convenient Synthesis of 2‐Amino‐3‐cyano‐4‐aryl‐1,4,5,6‐tetrahydrobenzo[h]chromenes Derivatives Using KF‐Al₂O₃ as Catalyst

Abstract

A series of new 2‐amino‐3‐cyano‐4‐aryl‐1,4,5,6‐tetrahydrobenzo[h]chromenes derivatives were synthesized by the reaction of malononitrile with 2‐arylmethylidene‐3, 4‐dihydro‐1(2H)‐naphthalenone in N,N‐dimethylformamide (DMF) at 80°C catalyzed by KF‐Al₂O₃. The structure of the product was confirmed by x‐ray analysis.

Keywords:

• Benzo[h]chromene
• Malononitrile
• KF‐Al₂O₃
• Synthesis

Acknowledgments

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

Notes

^aX‐Ray crystallography for 3a: Empirical formula C₂₁H₁₈N₂O₂, F_w = 330.37, T = 296(2) K, monoclinic, space group P2(1)/c, a = 6.478(1) Å, b = 25.557(5) Å, c = 10.549(2) Å, α = 90°, β = 96.75(2)°, γ = 90°, V = 1734.4(5) Å³, Z = 4, Dc = 1.265 Mg/m³, λ(MoKα) = 0.71073 Å, μ = 0.08 mm⁻¹, F(000) = 696. 1.59°< θ < 25.25°, R = 0.0367, wR = 0.0854. S = 0.891, Largest diff. peak and hole: 0.148 and −0.111 e. Å⁻³.