反应详情

A solution of n-butyl acetoacetate (0.10 mole), methyl 3-aminocrotonate (0.10 mole), 3-nitrobenzaldehyde (0.10 mole) and 150 mL of i-PrOH was refluxed overnight (18 h). The volatiles were removed in vacuo and the residue purified by flash chromatography (SiO2: EtOAc/Hex) to furnish the product in 49% yield as low melting, yellow solid: mp 69°-70° C.; 1H NMR (DMSO-d6) δ9.03 (s, 1H), 7.98 (m, 2H), 7.58 (m, 2H), 4.96 (s, 1H), 3.91 (m, 2H), 3,53 (s, 3H), 2.28 (s, 3H), 2.26 (s, 3H), 1.45 (p, 2H, J=6.6 Hz), 1.18 (m, 4H), and 0.83 (t, 3H, J=7.4 Hz); 13C NMR (DMSO-d6) δ167.0, 166.5, 150.1, 147.5, 146.5, 134.1, 129.7, 121.7, 121.1, 101.0, 100.9, 63.0, 50.8, 39.1, 30.2, 18.7, 18.3, and 13.5. Anal. Calcd for C20H24N2O6 : C, 61.85; H, 6.23; N, 7.21. Found: C, 62.02; H, 6.21; N, 6.95.

1. customThe volatiles were removed in vacuo
2. customthe residue purified by flash chromatography (SiO2: EtOAc/Hex)
3. customto furnish the product in 49% yield as low melting, yellow solid