Hydrochloric Acid → 4-Hydroxy-7-methylcoumarin

HRID 1155498Notes

Reaction equation

HRID 1155498 reaction equation
BrC[C:3]1[C:12]2[C:7](=[CH:8][C:9](OC)=[CH:10][CH:11]=2)OC(=O)C=1.[C:16]([O-:19])(=[O:18])[CH3:17].[Ca+2].[C:21]([O-])(=[O:23])C.Cl>C(O)(=O)C.C(O)C>[OH:23][C:21]1[C:9]2[C:10](=[CH:11][C:12]([CH3:3])=[CH:7][CH:8]=2)[O:18][C:16](=[O:19])[CH:17]=1

Participants

6

Reactant 3

HCID 313Hydrochloric AcidHCID 6116Calcium AcetateHCID 1218944-Bromomethyl-7-methoxycoumarin

Product 1

HCID 546853074-Hydroxy-7-methylcoumarin

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 702EthanolSolvent

Procedure

10 g of 4-bromomethyl-7-methoxycoumarin [produced according to Secrist et al., Biochem. Biophys. Res. Commun., 45, 1262 (1971)] are heated to boiling for 2.5 hours under reflux in 40 ml of glacial acetic acid together with 6 g of calcium acetate (free of water). The solution is brought to dryness in vacuo. The residue is heated to boiling in 50 ml of ethanol and 50 ml of concentrated hydrochloric acid for 1.5 hours under reflux. The volatile components are removed under reduced pressure. The residue is dissolved in chloroform. The resulting solution is made free of acids by extraction with diluted aqueous ammoniac and water and dried over annealed potassium carbonate. After removing the chloroform in vacuo, the residue is recrystallized from ethylacetate. In this manner 1.9 g (24.8 percent of the theoretically-calculated amount) of the title compound with a melting point of 179° to 182° C. are obtained.

Workup

  1. temperatureThe residue is heated
  2. customThe volatile components are removed under reduced pressure
  3. dissolutionThe residue is dissolved in chloroform
  4. extractionThe resulting solution is made free of acids by extraction with diluted aqueous ammoniac and water
  5. dry with materialdried over annealed potassium carbonate
  6. customAfter removing the chloroform in vacuo
  7. customthe residue is recrystallized from ethylacetate

Sources & evidence

ORD record
ord-f6b3844ed3924e6c90f376b81a3d0f14
Source dataset
uspto-grants-1981_11
Patent number
US04302438

Reaction notes

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