Sulfuric Acid → methyl 3-(3,4-dihydro-7-hydroxy-2-methyl-4-oxo-8-propyl-2H-1-benzopyran-2-yl)propanoate

HRID 868374

Reaction equation

HRID 868374 reaction equation
[OH:1][C:2]1[CH:18]=[CH:17][C:5]2[C:6](=[O:16])[CH2:7][C:8]([CH2:11][CH2:12][C:13]([OH:15])=[O:14])([CH3:10])[O:9][C:4]=2[C:3]=1[CH2:19][CH2:20][CH3:21].[CH3:22]OC(OC)OC.S(=O)(=O)(O)O>>[OH:1][C:2]1[CH:18]=[CH:17][C:5]2[C:6](=[O:16])[CH2:7][C:8]([CH2:11][CH2:12][C:13]([O:15][CH3:22])=[O:14])([CH3:10])[O:9][C:4]=2[C:3]=1[CH2:19][CH2:20][CH3:21]

Participants

4

Reactant 3

HCID 1118Sulfuric AcidHCID 9005Trimethyl orthoformateHCID 139207383-(3,4-dihydro-7-hydroxy-2-methyl-4-oxo-8-propyl-2H-1-benzopyran-2-yl)propanoic acid

Product 1

HCID 2801556methyl 3-(3,4-dihydro-7-hydroxy-2-methyl-4-oxo-8-propyl-2H-1-benzopyran-2-yl)propanoate

Procedure

A mixture of the title compound of Example 3 (4.3 g, 14.7 mmole), 6 ml of trimethylorthoformate, and 1.4 ml of sulfuric acid was stirred at room temperature for two hours. The reaction mixture was poured onto stirred ice/water and extracted with ethyl acetate. The organic phase was washed with water, dried over magnesium sulfate, and concentrated to an oil. The oil was purified by chromatography on silica gel, giving 3.7 g of the title compound as a crystalline solid, m.p. 101.5°-102.5°. Structure assignment was consistent with nmr and infrared spectra. ##STR7##

Workup

  1. additionThe reaction mixture was poured
  2. extractionextracted with ethyl acetate
  3. washThe organic phase was washed with water
  4. dry with materialdried over magnesium sulfate
  5. concentrationconcentrated to an oil
  6. customThe oil was purified by chromatography on silica gel

Sources & evidence

ORD record
ord-b1916b40b1b14b0894384837bbdfad28
Source dataset
uspto-grants-1988_10
Patent number
US04778903

Linked notes

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