Propanoic acid, 2-bromo-2-methyl-, ethyl ester → 2-Methyl-2-(tetrahydro-pyran-4-ylsulfanyl)-propionic acid ethyl ester

HRID 386864ノート

反応式

HRID 386864 の反応式
[O:1]1[CH2:6][CH2:5][CH:4]([S:7]C(=O)C)[CH2:3][CH2:2]1.[OH-].[K+].Br[C:14]([CH3:21])([CH3:20])[C:15]([O:17][CH2:18][CH3:19])=[O:16]>C(O)C>[CH2:18]([O:17][C:15](=[O:16])[C:14]([CH3:21])([S:7][CH:4]1[CH2:5][CH2:6][O:1][CH2:2][CH2:3]1)[CH3:20])[CH3:19]

参加物

5

反応物 3

HCID 11745Propanoic acid, 2-bromo-2-methyl-, ethyl esterHCID 14797Potassium HydroxideHCID 18533108S-Tetrahydro-2H-pyran-4-YL ethanethioate

生成物 1

HCID 597039552-Methyl-2-(tetrahydro-pyran-4-ylsulfanyl)-propionic acid ethyl ester収率 71%

試薬・触媒・溶媒 1

HCID 702Ethanol溶媒2 回

反応条件

温度
40 °C

実験手順

A solution of 153 g (0.96 mol) of thioacetic acid S-(tetrahydro-pyran-4-yl)ester in ethanol (3.5 L) is degassed with nitrogen over 0.5 h and 125 g (2.23 mol) of KOH are added. Then a solution of 250 mL (1.68 mol) of ethyl α-bromoisobutyrate in EtOH (1 L) are added over 0.5 h, during which the temperature increased to 40° C. The reaction is stirred for 18 h at room temperature under a nitrogen atmosphere. The reaction mixture is filtered, the solid is washed with ethanol (0.5 L) and the filtrate is concentrated under reduced pressure. The crude material is dryloaded onto silica and purified by dry-flash column chromatography (silica, eluent: n-heptanes, 2-10% ethyl acetate) to afford 158 g of 2-methyl-2-(tetrahydro-pyran-4-ylsulfanyl)-propionic acid ethyl ester as an orange-brown oil. Yield: 71%; ES-MS: m/z 233 [M+H]

後処理

  1. filtrationThe reaction mixture is filtered
  2. washthe solid is washed with ethanol (0.5 L)
  3. concentrationthe filtrate is concentrated under reduced pressure
  4. custompurified by dry-flash column chromatography (silica, eluent: n-heptanes, 2-10% ethyl acetate)

出典と根拠

ORDレコード
ord-b1821256fe614b75b8dc7bf4229ca1c3
出典データセット
uspto-grants-2013_02
特許番号
US08372874B2

反応ノート

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