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

HRID 1288253노트

반응식

HRID 1288253 반응식
[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

참가 물질

5

반응물 3

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

생성물 1

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

시약·촉매·용매 1

HCID 962Water용매

실험 절차

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°.

후처리

  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

출처 및 근거

ORD 기록
ord-e556ece14cde4f71980d829a28c4c145
출처 데이터셋
uspto-grants-1976_10
특허 번호
US03987185

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