反应详情

To a mixture of the product of Step E (0.03 g; 0.112 mmol), tert-butyl 5-formyl-2,2-dimethyl-1,3-dioxan-5-ylcarbamate (0.037 g; 0.115 mmol) and NaBH(OAc)3 (0.035 g; 0.17 mmol) in 1,2 dichloroethane (3 ml), Et3N (0.016 ml; 0.112 mmol) was added at room temperature, followed by AcOH (0.064 ml; 0.112 mmol). The resulting mixture was stirred overnight under N2. After dilution to 10 ml with Et2O, the mixture was washed with 1.M NaOH (2×2 ml), brine and dried over anhydrous MgSO4 and filtered. The filtrate was evaporated to dryness under reduced pressure. The residue was purified by FCC (SiO2; hexane/EtOAc 8:2) to give pure title compound (0.05 g; 92%) as colourless solid. 1H-NMR (CDCl3) 0.86 (tr, 3H, J=7 Hz); 1.25 (m, 10H); 1.41 (s, 3H); 1.44 (s, 9H); 1.47 (s, 3H); 1.57 (m, 2H); 2.56 (tr, 2H, J=7.92 Hz); 3.18 (s, 2H): 3.79 (d, 2H, J=11.7 Hz); 4.05 (s, 4H); 4.14 (d, 2H, J=11.7 Hz); 5.03 (s, 1H); 6.98 (s, 1H); 6.99 (d, 1H, J=8.14 Hz); 7.06 (d, 1H, J=8.14 Hz).

1. additionwas added at room temperature
2. washAfter dilution to 10 ml with Et2O, the mixture was washed with 1.M NaOH (2×2 ml), brine
3. dry with materialdried over anhydrous MgSO4
4. filtrationfiltered
5. customThe filtrate was evaporated to dryness under reduced pressure
6. customThe residue was purified by FCC (SiO2; hexane/EtOAc 8:2)