反应 #172729

ord-8b80b1428ebb418897ce4b40a1e944d8

反应方程式

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
收率 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
收率 97.0%

反应物

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

试剂

无

溶剂

CN(C)C=O
DMF

反应条件

温度
60°CELSIUS
详细条件
See reaction.notes.procedure_details.

后处理

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

实验过程

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).

来源

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