反応 #40604

反応方程式

39

(2S,4aR,6aR,7R,9S,10aS,10bR)-9-(Amino)-2-(3-furanyl)-dodecahydro-6a,10b-dimethyl-4,10-dioxo-2H-naphtho[2,1-c]pyran-7-carboxylic acid methyl ester

benzoyl chloride

MeOH

→

10

収率 67.0%

(2S,4aR,6aR,7R,9S,10aS,10bR)-9-(isobutyryloxy)-2-(3-furanyl)-dodecahydro-6a,10b-dimethyl-4,10-dioxo-2H-naphtho[2,1-c]pyran-7-carboxylic acid methyl ester

収率 67.0%

溶媒

CH2Cl2

反応条件

後処理

1. 1
   その他the solvent was removed under reduced pressure
2. 2
   workup.ADDITIONCH2Cl2 (25 mL) was added to the residue
3. 3
   洗浄the solution was washed with 10% HCl (2×20 mL), H2O (3×20 mL), and saturated NaCl (3×20 mL)
4. 4
   乾燥dried (Na2SO4)
5. 5
   その他Removal of the solvent under reduced pressure

実験手順

A solution of 39 (0.10 g, 0.26 mmol), benzoyl chloride (0.11 g, 0.78 mmol) and DMAP (0.08 g, 0.78 mmol) in CH2Cl2 (20 mL) was stirred at room temperature for 2 h. Absolute MeOH (15 mL) was added and the solvent was removed under reduced pressure. CH2Cl2 (25 mL) was added to the residue and the solution was washed with 10% HCl (2×20 mL), H2O (3×20 mL), and saturated NaCl (3×20 mL) and dried (Na2SO4). Removal of the solvent under reduced pressure afforded 0.09 g (67%) of 10 as a white crystalline solid, mp 155-157° C. (EtOAc/n-hexanes); 1H NMR (CDCl3): δ 1.44 (3H, s); 1.50 (3H, s); 1.63 (3H, m); 1.82 (1H, dd, J=2.1, 10.5); 2.0 (1H, m); 2.12 (1H, dd, J=2.7, 8.4); 2.17 (1H, m); 2.32 (1H, s); 2.48 (1H, dd, J=5.4, 13.2); 2.79 (1H, dd, J=3.3, 6.9); 2.87 (1H, dd, J=2.7, 13.5); 3.71 (3H, s); 4.69 (1H, m); 5.55 (1H, dd, J=5.1, 11.4); 6.37 (1H, dd, J=0.9, 1.8); 7.1 (1H, d, J=6.0); 7.39 (1H, t, J=1.8); 7.41 (1H, dd, J=0.9, 1.8); 7.46 (1H, m); 7.53 (1H, tt, J=1.5, 2.7, 7.2); 7.80 (1H, t, J=2.4); 7.82 (1H, t, J=1.2.

出典