反应详情

A 500 mL round bottom flask was charged with 2-(S)-(2,2,2-trifluoroacetylamino)-butyric acid (5.0 g, 0.025 mol), 1-hydroxybenzotriazole hydrate (4.5 g, 0.033 mol), N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (6.4 g, 0.033 mol), 4-(dimethylamino)pyridine (0.02 g, 0.163 mmol), and dimethylformamide (95 mL). To the resulting mixture was then added triethylamine (10.6 mL, 0.076 mol) and pent-4-yn-1-amine (2.7 g, 0.033 mol). The resulting mixture was stirred at room temperature for 22 h, then concentrated in vacuo and the resulting residue purified via flash silica gel chromatography (Analogix IF-280, SF65-400 g column, gradient 90:10-40:60 Heptane:EtOAc) to yield (S)—N-(pent-4-ynyl)-2-(2,2,2-trifluoroacetamido)butanamide. 1H NMR (300 MHz, CDCl3) δ 4.46-4.53 (m, 1H), 3.32-3.48 (m, 2H), 2.23-2.29 (m, 2H), 2.00 (s, 1H), 1.86-1.98 (m, 2H), 1.71-1.83 (m, 2H), and 0.91-0.98 (m, 3H).

1. concentrationconcentrated in vacuo
2. customthe resulting residue purified via flash silica gel chromatography (Analogix IF-280