Neopentyl glycol → 2-Carboxy-5,5-dimethyl-1,3-dioxane

HRID 1784129ノート

反応式

HRID 1784129 の反応式
O.[C:2]([OH:6])(=[O:5])[CH:3]=[O:4].[CH3:7][C:8]([CH3:13])([CH2:11]O)[CH2:9][OH:10]>C1C=CC=CC=1>[C:2]([CH:3]1[O:10][CH2:9][C:8]([CH3:13])([CH3:11])[CH2:7][O:4]1)([OH:6])=[O:5]

参加物

4

反応物 2

HCID 31344Neopentyl glycolHCID 15620607Glyoxylic acid, monohydrate

生成物 1

HCID 114351012-Carboxy-5,5-dimethyl-1,3-dioxane収率 73.4%

試薬・触媒・溶媒 1

HCID 241Benzene溶媒

実験手順

Following a general procedure,23 a mixture of glyoxylic acid monohydrate (5.0 g, 54 mmol), 2,2-dimethyl 1,3-propanediol (8.5 g, 81 mmol) and Amberlyst-15 ion-exchange resin (100 mg) in benzene (140 mL) was refluxed for 15 h in a flask fitted with a Dean-Stark apparatus. The reaction mixture was filtered. The filtrate was concentrated and then refluxed with 20% aqueous NaOH (50 mL) for 30 min. The resulting alkaline solution was extracted with ether and neutralized in the cold with dilute HCl. At the end the pH was brought to ˜1.0 using H3PO4. The acidified aqueous layer was extracted with ether. The extracts were combined, dried (Na2SO4) and concentrated to afford a white solid (6.349 g, 73%): mp 58-60° C.; 1H NMR δ 0.80 (s, 3H), 1.22 (s, 3H), 3.57 (d, J=12.0 Hz, 2H), 3.79 (d, J=12.0 Hz, 2H), 4.97 (s, 1H); 13C NMR δ 169.1, 124.7, 95.8, 77.5, 30.6, 23.0, 21.9; FAB-MS obsd 161.0806, calcd 161.0814 (C7H12O4).

後処理

  1. temperaturewas refluxed for 15 h in a flask
  2. customfitted with a Dean-Stark apparatus
  3. filtrationThe reaction mixture was filtered
  4. concentrationThe filtrate was concentrated
  5. temperaturerefluxed with 20% aqueous NaOH (50 mL) for 30 min
  6. extractionThe resulting alkaline solution was extracted with ether
  7. extractionThe acidified aqueous layer was extracted with ether
  8. dry with materialdried (Na2SO4)
  9. concentrationconcentrated

出典と根拠

ORDレコード
ord-ac1066e2a00a46a68a42da26e6ac36ce
出典データセット
uspto-grants-2009_03
特許番号
US07501507B2

反応ノート

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