Ethylene Glycol → 2-(4-Bromothiophen-2-yl)-1,3-dioxolane
反応式
[Br:1][C:2]1[CH:3]=[C:4]([CH:7]=[O:8])[S:5][CH:6]=1.[CH2:9](O)[CH2:10][OH:11]>C1(C)C=CC=CC=1.C1(C)C=CC(S(O)(=O)=O)=CC=1>[Br:1][C:2]1[CH:3]=[C:4]([CH:7]2[O:11][CH2:10][CH2:9][O:8]2)[S:5][CH:6]=1参加物
5
実験手順
A mixture of 4-bromo-thiophene-2-carbaldehyde (175 g, 916 mmol), ethylene glycol (71.1 g, 1.15 mol) and p-toluenesulfonic acid (0.19 g, 1.0 mmol) in toluene (250 mL) is heated to reflux for 7 h using a Dean-Stark apparatus. After cooling, the solution is washed with aq NaHCO3, dried over Na2SO4, filtered and concentrated in vacuo. The residue is distilled to give 2-(4-bromo-thiophen-2-yl)-[1,3]dioxolane (210.6 g, 98%) as a colorless liquid: bp 133-143/11-14 mBar; 1H NMR (CDCl3, 300 MHz) δ 7.21 (s, 1 H), 7.04 (s, 1 H), 6.04 (s, 1 H), 3.95-4.18 (m, 4 H).
後処理
- temperatureis heated
- temperatureto reflux for 7 h
- temperatureAfter cooling
- washthe solution is washed with aq NaHCO3
- dry with materialdried over Na2SO4
- filtrationfiltered
- concentrationconcentrated in vacuo
- distillationThe residue is distilled
出典と根拠
- ORDレコード
- ord-3ef4551a5af34ca18169c18ad9c958ae
- 出典データセット
- uspto-grants-2008_04
- 特許番号
- US07361671B2
反応ノート
読み込み中…