Ethylene Glycol → 2-Methyl-2-(4-methylphenyl)-1,3-dioxolane

HRID 250522

反応式

HRID 250522 の反応式
[CH3:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([CH3:10])=[O:9])=[CH:4][CH:3]=1.C1(C)C=CC(S(O)(=O)=O)=CC=1.[CH2:22](O)[CH2:23][OH:24]>C1(C)C=CC=CC=1>[CH3:10][C:8]1([C:5]2[CH:6]=[CH:7][C:2]([CH3:1])=[CH:3][CH:4]=2)[O:24][CH2:23][CH2:22][O:9]1

参加物

5

反応物 3

HCID 174Ethylene GlycolHCID 6101p-Toluenesulfonic acidHCID 8500p-METHYLACETOPHENONE

生成物 1

HCID 27554692-Methyl-2-(4-methylphenyl)-1,3-dioxolane収率 79.1%

試薬・触媒・溶媒 1

HCID 1140Toluene溶媒

実験手順

A mixture of 4-methylacetophenone (1.00 g, 7.45 mmol), p-toluenesulfonic acid (133 mg, 0.745 mmol) and ethylene glycol (1.20 mL, 22.4 mmol) in dry toluene (20 mL) was heated at reflux with a Dean-Stark apparatus under nitrogen for 24 h. The mixture was allowed to cool to room temperature and the solvent was evaporated in vacuo. The residue was taken up in ether (20 mL) and the solution was washed with saturated sodium bicarbonate solution (2×10 mL) and brine (1×10 mL), then dried (Na2SO4) and concentrated under reduced pressure. Flash column chromatography of the residue, eluting with 37% aqueous ammonia:ether:hexane (0.02:1:6) afforded 2-methyl-2-(4-methylphenyl)-1,3-dioxolane (23) as a colourless oil (1.05 g, 59%). 1H nmr (200 MHz, CDCl3) 1.65 (s, 3H, CH3), 2.35 (s, 3H, ArCH3), 3.74-3.86 (m, 2H, OCH2), 3.94-4.06 (m, 2H, OCH2), 7.15 (d, J=8.2 Hz, 2H, 2×ArH), 7.37 (d, J=8.2 Hz, 2H, 2×ArH).

後処理

  1. temperaturewas heated
  2. temperatureat reflux with a Dean-Stark apparatus under nitrogen for 24 h
  3. customthe solvent was evaporated in vacuo
  4. washthe solution was washed with saturated sodium bicarbonate solution (2×10 mL) and brine (1×10 mL)
  5. dry with materialdried (Na2SO4)
  6. concentrationconcentrated under reduced pressure
  7. washFlash column chromatography of the residue, eluting with 37% aqueous ammonia:ether:hexane (0.02:1:6)

出典と根拠

ORDレコード
ord-125d60b86bf04bc18b8c7532c6023856
出典データセット
uspto-grants-2011_01
特許番号
US07863313B2

関連ノート

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