3,4-dihydro-2H-pyran → 2-(Tetrahydro-pyran-2-yloxy)-cyclopentanecarboxylic acid ethyl ester

HRID 854771ノート

反応式

HRID 854771 の反応式
[CH2:1]([O:3][C:4]([CH:6]1[CH2:10][CH2:9][CH2:8][CH:7]1[OH:11])=[O:5])[CH3:2].[O:12]1[CH:17]=[CH:16][CH2:15][CH2:14][CH2:13]1.C1(C)C=CC(S([O-])(=O)=O)=CC=1.[NH+]1C=CC=CC=1>C(Cl)Cl>[CH2:1]([O:3][C:4]([CH:6]1[CH2:10][CH2:9][CH2:8][CH:7]1[O:11][CH:13]1[CH2:14][CH2:15][CH2:16][CH2:17][O:12]1)=[O:5])[CH3:2]

参加物

5

反応物 3

HCID 80803,4-dihydro-2H-pyranHCID 275611Ethyl 2-hydroxycyclopentanecarboxylateHCID 466102Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1)

生成物 1

HCID 665594152-(Tetrahydro-pyran-2-yloxy)-cyclopentanecarboxylic acid ethyl ester収率 87.7%

試薬・触媒・溶媒 1

HCID 6344Dichloromethane溶媒

反応条件

温度
25 °C

実験手順

A solution of 2-hydroxy-cyclopentanecarboxylic acid ethyl ester (3.5 g, 22.12 mmol) in methylene chloride (147.5 mL) was treated with 3,4-dihydro-2H-pyran (3.03 mL, 33.1 mmol) and pyridiniump-toluenesulfonate (556 mg, 2.21 mmol). This solution was stirred at 25° C. for 5 h. The reaction was then washed with a half-saturated aqueous sodium chloride solution (2×75 mL), dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230-400 mesh, 90/10 hexanes/ethyl acetate) afforded 2-(tetrahydro-pyran-2-yloxy)-cyclopentanecarboxylic acid ethyl ester (4.7 g, 87.7%) as a clear liquid: EI-HRMS m/e calcd for C13H22O4 (M+) 242.1518. found 242.1521.

後処理

  1. washThe reaction was then washed with a half-saturated aqueous sodium chloride solution (2×75 mL)
  2. dry with materialdried over sodium sulfate
  3. filtrationfiltered
  4. concentrationconcentrated in vacuo

出典と根拠

ORDレコード
ord-aa2f61d0907c4ef5b6255b528d982716
出典データセット
uspto-grants-2007_08
特許番号
US07259166B2

反応ノート

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