反应详情

温度

50 °C

To a 250-mL round-bottomed flask was added 8 (1.37 g, 8 mmol), suspended in 40 mL of dichloroethane; then trimethylacetyl chloride (1.99 mL, 16 mmol), DMAP (0.13 g, 1 mmol) and triethylamine (2.68 mL) were added. The mixture was stirred overnight at 50° C. The resulting mixture was cooled, diluted with dichloromethane (50 mL), washed with brine (40 mL×2), dried over Na2SO4 and concentrated in vacuo. To this solution were added methylene chloride (30 mL) and silica gel (5 g) and the solvent evaporated. The silica gel plug obtained was loaded onto a silica gel column and eluted with 9:1 ethyl acetate/n-hexane The fractions containing the product (TLC) were pooled and the solvent was evaporated to afford 1.33 g (67%) of9 as a white solid: TLC Rf0.47 (MeOH/CHCl3, 1:10); mp 156-157° C.; 1H NMR (DMSO-d6) δ 1.19 (s, 9 H), 2.29 (s, 3 H), 5.97 (s, 1 H), 10.72 (s, 1 H), 11.78 (s, 1 H), 11.87 (s, 1 H). Anal. (C12H16N4O20.15CH3COCH3) C, H, N.

1. temperatureThe resulting mixture was cooled
2. washwashed with brine (40 mL×2)
3. dry with materialdried over Na2SO4
4. concentrationconcentrated in vacuo
5. additionTo this solution were added methylene chloride (30 mL) and silica gel (5 g)
6. customthe solvent evaporated
7. customThe silica gel plug obtained
8. washeluted with 9:1 ethyl acetate/n-hexane The fractions
9. additioncontaining the product (TLC)
10. customthe solvent was evaporated
11. customto afford 1.33 g (67%) of9 as a white solid