三氯甲烷 → (-)-Acetic acid cis-4-benzyloxy-cyclopent-2-enyl ester

HRID 2555

反应方程式

HRID 2555 反应方程式
[CH2:1]([O:8][C@@H:9]1[CH2:13][C@H:12]([OH:14])[CH:11]=[CH:10]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(N(CC)CC)C.[C:22]([O:25][CH:26]=[CH2:27])(=[O:24])[CH3:23].C(Cl)(Cl)Cl>COC(C)(C)C>[CH2:1]([O:8][C@@H:9]1[CH2:13][C@H:12]([OH:14])[CH:11]=[CH:10]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH2:1]([O:8][C@@H:9]1[CH2:13][C@H:26]([O:25][C:22](=[O:24])[CH3:23])[CH:27]=[CH:10]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

参与物

7

反应物 4

HCID 6212三氯甲烷2 次HCID 7904乙酸乙烯酯HCID 8471三乙胺HCID 15812323(1S,4R)-4-(Benzyloxy)cyclopent-2-en-1-ol

产物 2

HCID 15812323(1S,4R)-4-(Benzyloxy)cyclopent-2-en-1-ol收率 29%HCID 86752290(-)-Acetic acid cis-4-benzyloxy-cyclopent-2-enyl ester收率 70%

试剂、催化剂与溶剂 1

HCID 15413甲基叔丁基醚溶剂

实验过程

Cis-4-benzyloxy-cyclopent-2-enol (500 mg, prepared in example 16) is dissolved in tert-butyl methyl ether (8.6 mL, anhydrous). To the solution is added triethylamine (0.7 eq), pancreatin (3 wt eq, available from Sigma Chemical Company), and vinyl acetate (5 eq). The reaction is allowed to stir for 7 hours at room temperature. The reaction is then filtered through diatomaceous earth and the filtrate is concentrated under vacuum. The products are separated by chromatography on silica gel (20% ethyl acetate/hexane) to provide (-)-cis-4-benzyloxy-cyclopent-2-enol (A) (147 mg, 29% yield) [α]20D -12°, (c=1.09, chloroform), and (-)-acetic acid cis-4-benzyloxy-cyclopent-2-enyl ester (B) (427 mg, 70% yield),[α]20D =-5.2°, (c=0.97, chloroform), 1 H NMR (CDCl3) δ 7.3 (m, 5H), 6.13 (d, 1H, J=5 Hz), 5.99 (d, 1H, J=5 Hz), 5.5 (m, 1H), 4.59 (d, 1H, J=11.8 Hz), 4.54 (d, 1H, J=11.8 Hz), 4.5 (m, 1H), 2.78 (d appt, 1H, J=7.2, 14.3 Hz), 2.05 (s, 3H), 1.76 (d appt, 1H, J=4.4, 14.3 Hz); 13C NMR (CDCl3) δ171.1, 138.5, 136.4, 133.1, 128.7, 128, 127.9, 81.4, 77.1, 71.2, 37.8, 21.4.

后处理

  1. filtrationThe reaction is then filtered through diatomaceous earth
  2. concentrationthe filtrate is concentrated under vacuum
  3. customThe products are separated by chromatography on silica gel (20% ethyl acetate/hexane)

来源与证据

ORD记录
ord-443e36063c0a47edae71957a9c2af350
来源数据集
uspto-grants-1998_03
专利号
US05728899

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