反应详情

2,3-Dichloroquinoxaline (18.05 g, 90.7 mmol) is added to a solution of crude 1a (11.7 g, 99.8 mmol) and Et3N (19 ml, 13.8 g, 136 mmol) in dioxane (210 ml). The solution obtained is heated at reflux (under N2) for 6 h, it is then cooled to room temperature. Et3N, HCl is eliminated by filtration and the filtrate is concentrated under reduced pressure. The dark orange residue is purified by chromatography on a silica column, eluent: CH2Cl2/MeOH (100:0→99:1), to obtain a yellow solid (12.14 g, 48%); 1H NMR (100 MHz, CDCl3) δ: 0.72 (d, 3H), 0.78 (d, 3H), 1.60 (m, 3H), 3.68 (m, 4H), 5.82 (t, 1H), 7.58 (m, 4H); 13C NMR (25 MHz, CDCl3) δ: 22.17, 23.35, 24.60, 44.32, 48.62, 69.67, 125.30, 125.62, 127.91, 130.36, 136.52, 137.92, 140.59, 148.62. Analysis calculated for C14H18N3OCl: C, 60.10; H, 6.49; N, 15.02. Experimental: C, 59.87; H, 6.62; N, 15.25.

1. customThe solution obtained
2. temperatureis heated
3. filtrationEt3N, HCl is eliminated by filtration
4. concentrationthe filtrate is concentrated under reduced pressure
5. customThe dark orange residue is purified by chromatography on a silica column, eluent