反应详情

Step A (2): A solution of LiOH (2 M, 0.73 g, 30.4 mmol) in 15 mL H2O was added to a solution of methyl 2-(2-oxopyrrolidin-1-yl)pent-4-enoate (2.0 g, 10.1 mmol) from step A(1) in THF (15 mL) at room temperature. The mixture was stirred at room temperature for 16 h. Poured into 1 N HCl. Extracted with EtOAc (3×250 mL). Washed combined organics with brine, dried with Na2SO4 After concentration in vacuo, dried on high-vacuum for ˜3 h to give 1.5 g (81%) of 2-(2-oxopyrrolidin-1-yl)pent-4-enoic acid as a beige solid: LC-MS (M+H)+=184.1; 1H NMR (300 MHz, CDCl3) δ 11.85 (s, 1H), 5.47-5.81 (m, 1H), 4.91-5.25 (m, 2H), 4.81 (dd, J=11.14, 4.73 Hz, 1H), 3.45-3.59 (m, 1H), 3.25-3.40 (m, 1H), 2.59-2.83 (m, 1H), 2.30-2.52 (m, 3H), 1.80-2.12 (m, 2H).

1. extractionExtracted with EtOAc (3×250 mL)
2. washWashed
3. dry with materialdried with Na2SO4
4. concentrationAfter concentration in vacuo
5. customdried on high-vacuum for ˜3 h