Hydrochloric Acid → 8-Methoxy-1-oxo-1H-2-benzopyran-3-carboxylic acid

HRID 1288253ノート

反応式

HRID 1288253 の反応式
[C:1]([C:4]1[C:22]([O:23][CH3:24])=[CH:21][CH:20]=[CH:19][C:5]=1[CH:6]=[C:7]1[C:11](=[O:12])[O:10]C(C2C=CC=CC=2)=N1)([OH:3])=[O:2].O1C=CNC1=O.[OH-].[Na+].Cl>O>[CH3:24][O:23][C:22]1[C:4]2[C:1](=[O:3])[O:2][C:7]([C:11]([OH:10])=[O:12])=[CH:6][C:5]=2[CH:19]=[CH:20][CH:21]=1

参加物

5

反応物 3

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 68143331oxazolone 4-(2-carboxy-3-methoxybenzylidene)-2-phenyl-5(4H)-oxazolone

生成物 1

HCID 215047378-Methoxy-1-oxo-1H-2-benzopyran-3-carboxylic acid

試薬・触媒・溶媒 1

HCID 962Water溶媒

実験手順

A solution of the oxazolone of Example 4 (1.80 g., 5.57 mM) and 3.06 g. of sodium hydroxide in 15.2 ml. of water is refluxed under nitrogen for two hours. The resulting solution is cooled, acidified with concentrated hydrochloric acid, and refluxed for 0.5 hour. The solution is cooled and filtered to separate the precipitated solids. The dried solid is triturated with 2 ml. of cold methanol (to remove benzoic acid) and filtered to separate the product, m.p. 251°-253°. Recrystallization from 12 ml. of methanol (charcoal) gives 8-methoxy-1-oxo-1H-2-benzopyran-3-carboxylic acid as a white solid, m.p. 255°-256°.

後処理

  1. temperatureThe resulting solution is cooled
  2. temperaturerefluxed for 0.5 hour
  3. temperatureThe solution is cooled
  4. filtrationfiltered
  5. customto separate the precipitated solids
  6. customThe dried solid is triturated with 2 ml
  7. filtrationof cold methanol (to remove benzoic acid) and filtered
  8. customto separate the product, m.p. 251°-253°
  9. customRecrystallization from 12 ml

出典と根拠

ORDレコード
ord-e556ece14cde4f71980d829a28c4c145
出典データセット
uspto-grants-1976_10
特許番号
US03987185

反応ノート

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