反応 #172729

ord-8b80b1428ebb418897ce4b40a1e944d8

反応方程式

C=C(C)[C@@H]1CC[C@]2(C(=O)O)CC[C@]3(C)[C@H](CC[C@@H]4[C@@]5(C)CC[C@H](O)C(C)(C)[C@@H]5CC[C@]43C)[C@@H]12
betulinic acid
O=C([O-])[O-].[K+].[K+]
potassium carbonate
BrCc1ccccc1
benzyl bromide
→
C=C(C)[C@@H]1CC[C@]2(C(=O)OCc3ccccc3)CC[C@]3(C)[C@H](CC[C@@H]4[C@@]5(C)CC[C@H](O)C(C)(C)[C@@H]5CC[C@]43C)[C@@H]12
title compound
収率 97.0%
C=C(C)[C@@H]1CC[C@]2(C(=O)OCc3ccccc3)CC[C@]3(C)[C@H](CC[C@@H]4[C@@]5(C)CC[C@H](O)C(C)(C)[C@@H]5CC[C@]43C)[C@@H]12
(1R,3aS,5aR,5bR,7aR,9S,11aR,11bR,13aR,13bR)-benzyl 9-hydroxy-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)icosahydro-1H-cyclopenta[a]chrysene-3a-carboxylate
収率 97.0%

反応物

C=C(C)[C@@H]1CC[C@]2(C(=O)O)CC[C@]3(C)[C@H](CC[C@@H]4[C@@]5(C)CC[C@H](O)C(C)(C)[C@@H]5CC[C@]43C)[C@@H]12
betulinic acid
O=C([O-])[O-].[K+].[K+]
potassium carbonate
BrCc1ccccc1
benzyl bromide

試薬

なし

溶媒

CN(C)C=O
DMF

反応条件

温度
60°CELSIUS
詳細条件
See reaction.notes.procedure_details.

後処理

  1. 1
    温度it was cooled to rt
  2. 2
    その他to precipitate
  3. 3
    温度upon cooling
  4. 4
    その他the solids that formed
  5. 5
    ろ過were collected by filtration

実験手順

To a suspension of betulinic acid (12 g, 26.3 mmol) and potassium carbonate (7.26 g, 52.6 mmol) in DMF (150 mL) was added benzyl bromide (3.28 mL, 27.6 mmol). The mixture was heated to 60° C. for 3.5 h, and then it was cooled to rt. Solids started to precipitate upon cooling. The mixture was diluted water (200 mL) and the solids that formed were collected by filtration to give the title compound (13.92 g, 25.5 mmol, 97% yield) as a white solid. 1H NMR (500 MHz, CHLOROFORM-d) δ ppm 7.39-7.28 (m, 5H), 5.16-5.06 (m, 2H), 4.71 (d, J=1.83 Hz, 1H), 4.59 (s, 1H), 3.17 (ddd, J=11.44, 5.65, 5.49 Hz, 1H), 3.01 (td, J=10.99, 4.88 Hz, 1H), 2.27 (ddd, J=12.36, 3.20, 3.05 Hz, 1H), 2.21-2.13 (m, 1H), 1.93-1.81 (m, 2H), 1.67 (s, 3H), 0.95 (s, 3H), 0.93 (s, 3H), 1.71-0.82 (m, 20H), 0.79 (s, 3H), 0.75 (s, 3H), 0.74 (s, 3H).

出典

DOI: 10.6084/m9.figshare.5104873.v1特許: US08846647B2uspto-grants-2014_09