三氯甲烷 → (+)-Acetic acid cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enyl ester

HRID 2550

反应方程式

HRID 2550 反应方程式
[O:1]1[CH2:6][CH2:5][CH2:4][CH2:3][CH:2]1[O:7][C@@H:8]1[CH2:12][C@H:11]([OH:13])[CH:10]=[CH:9]1.C(N(CC)CC)C.[C:21](OC=C)(=[O:23])[CH3:22].C(Cl)(Cl)Cl>COC(C)(C)C>[O:1]1[CH2:6][CH2:5][CH2:4][CH2:3][CH:2]1[O:7][C@@H:8]1[CH2:12][C@H:11]([O:13][C:21](=[O:23])[CH3:22])[CH:10]=[CH:9]1

参与物

6

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 13623252cis-4-Tetrahydropyranyloxy 2-cyclopentenol2 次

产物 1

HCID 13623284(+)-Acetic acid cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enyl ester收率 45%

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-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enol (1.091 g, 5.92 mmol, prepared in example 6) is dissolved in tert-butyl methyl ether (8.6 mL, anhydrous). To the solution is added triethylamine (0.59 mL, 4.2 mmol), pancreatin (3.2 g, available from Sigma Chemical Company), and vinyl acetate (2.7 mL, 29 mmol). 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 (10% to 20% ethyl acetate/hexane) to provide (-)-acetic acid cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enyl ester (B, 601 mg, 45% yield, 91% ee) [α]D =-19.8°,(c=1.00, chloroform) as a yellow oil and (-)-cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enol (A, 560 mg, 50% yield, 94% ee), [α]D =-9.9°, (c=1.06, chloroform) as a yellow oil.

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 (10% to 20% ethyl acetate/hexane)

来源与证据

ORD记录
ord-23a5242235f843fa9d331c47debf3305
来源数据集
uspto-grants-1998_03
专利号
US05728899

关联笔记

加载中…