Hydrochloric Acid → 4-Hydroxy-7-methylcoumarin

HRID 2422481Notes

Reaction equation

HRID 2422481 reaction equation
[H-].[Na+].[OH:3][C:4]1[CH:9]=[C:8]([CH3:10])[CH:7]=[CH:6][C:5]=1[C:11](=[O:13])[CH3:12].[C:14](=O)(OCC)[O:15]CC.Cl>C1(C)C=CC=CC=1>[OH:13][C:11]1[C:5]2[C:4](=[CH:9][C:8]([CH3:10])=[CH:7][CH:6]=2)[O:3][C:14](=[O:15])[CH:12]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 7766Diethyl CarbonateHCID 24758Sodium hydrideHCID 813382'-Hydroxy-4'-methylacetophenone

Product 1

HCID 546853074-Hydroxy-7-methylcoumarin

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent3×

Conditions

Temperature
80 °C

Procedure

To a mechanically stirred suspension of sodium hydride (60% in oil, 30 g, 749 mmol) in toluene (400 mL), heated at 80° C., a solution of the commercially available 2′-hydroxy-4′-methylacetophenone (50 g, 0.333 mmol) in 150 mL of toluene was added dropwise over 1 h. After complete addition, the mixture was stirred 15 min and a solution of diethyl carbonate (81 mL, 666 mmol) in toluene (500 mL) was added dropwise over 1 h. The reaction mixture was then stirred overnight at reflux. After cooling, the reaction mixture was poured into 800 mL of 2N HCl. The precipitate formed was collected by filtration, co-evaporated twice with toluene and dried under high vacuum at 55° C. 1H NMR (400 MHz, acetone-d6): 11.1 (bs, 1H), 7.76 (d, 1H), 7.18 (d, 1H), 7.14 (s, 1H), 5.60 (s, 1H), 2.47 (s, 3H).

Workup

  1. additionAfter complete addition
  2. stirringThe reaction mixture was then stirred overnight
  3. temperatureat reflux
  4. temperatureAfter cooling
  5. customThe precipitate formed
  6. filtrationwas collected by filtration
  7. customdried under high vacuum at 55° C

Sources & evidence

ORD record
ord-51e75555139f4c4e9129d87f44530ea9
Source dataset
uspto-grants-2011_06
Patent number
US07960409B2

Reaction notes

Loading…