反应详情

To a stirred suspension of CuBr.SMe2 (2.74 g, 13.33 mmol) in Et2O (100 mL) under Ar at −70° C., was added methyl lithium (1:6 M in Et2O; 15.13 mL, 24.21 mmol) dropwise and the solution allowed to warm to RT. The mixture was re-cooled to −70° C., to which was added a solution of (S)-2-(trityl-amino)-butyraldehyde (2 g, 6.05 mmol) in Et2O (25 mL) dropwise with stirring. The reaction mixture was stirred at this temperature for 2 h and then at −55° C. for 4 h, when TLC (8:2 hexane/Et2O) indicated that the reaction had gone to completion. To the reaction mixture was added a saturated aqueous solution of NH4Cl (100 mL) and allowed to warm to RT over 16 h. The reaction mixture was extracted with Et2O (2×200 mL), and the combined organic phase washed with brine (50 mL), dried (MgSO4) and evaporated in vacuo. The residue was purified by silica gel column chromatography, eluted with hexane/Et20 (8:2) to afford the title compounds as a light yellow oil (1.37 g, 66%). 1H-NMR (d6-DMSO, 250 MHz): δ 0.44-0.58 (m, 3H, —NHCH(CH2CH3)CH(CH3)OH), 0.99-1.12 (m, 5H, —NHCH(CH2CH3)CH(CH3)OH+—NHCH(CH2CH3)CH(CH3)OH), 2.01 (m, 1H, —NHCH(CH2CH3)CH(CH3)OH), 3.22-3.43 (m, 1H, —NHCH(CH2CH3)CH(CH3)OH), 4.41 (d, 1H, J=3.31 Hz, —NHCH(CH2CH3)CH(CH3)OH), 7.14-7.56 (m, 15H, 3×Bz).

1. temperatureThe mixture was re-cooled to −70° C., to which
2. stirringThe reaction mixture was stirred at this temperature for 2 h
3. temperatureto warm to RT over 16 h
4. extractionThe reaction mixture was extracted with Et2O (2×200 mL)
5. washthe combined organic phase washed with brine (50 mL)
6. dry with materialdried (MgSO4)
7. customevaporated in vacuo
8. customThe residue was purified by silica gel column chromatography
9. washeluted with hexane/Et20 (8:2)