反应详情

A mixture of the product of Step E (0.084 g; 0.186 mmol) in 60% TFA/CH2Cl2 (1.5 ml) was stirred for 5 min at room temperature under N2, then diluted to 4 ml with EtOH, stirred for additional 15 min and evaporated to dryness under reduced pressure. To it, tert-butyl 5-formyl-2,2-dimethyl-1,3-dioxan-5-ylcarbamate (0.05 g; 0.193 mmol) was added followed by NaBH(OAc)3 (0.13 g; 0.58 mmol) and 1,2-dichloroethane (1.5 ml). The resulting mixture was stirred for 1 h at room temperature, diluted to 15 ml with EtOAc, washed with 10% NaOH (2×5 ml), brine, dried over anhydrous MgSO4, filtered and filtrate evaporated to dryness. The residue was purified by FCC (SiO2; CH2Cl2:EtOAc 8:2) to give the title compound (0.07 g; 63%) as off white foam. 1H-NMR (CDCl3) 1.38-1.61 (m, 21H); 3.21 (s, 2H); 3.82 (d, 2H, J=12 Hz); 4.05-4.24 (m, 10H); 4.98 (broad s, 1H); 6.97 (d, 1H, J=9 Hz); 7.2-7.3 (m, 1H+CDCl3); 7.66 (d, 1H, J=3 Hz); 7.78 (dd, 1H, J=3, 6 Hz); 7.96-8.02 (m, 2H).

1. stirringstirred for additional 15 min
2. customevaporated to dryness under reduced pressure
3. stirringThe resulting mixture was stirred for 1 h at room temperature
4. washwashed with 10% NaOH (2×5 ml), brine
5. dry with materialdried over anhydrous MgSO4
6. filtrationfiltered
7. customfiltrate evaporated to dryness
8. customThe residue was purified by FCC (SiO2; CH2Cl2:EtOAc 8:2)