Boron trifluoride etherate → Methyl 1-hydroxy-7-methoxynaphthalene-2-carboxylate

HRID 35661Notes

Reaction equation

HRID 35661 reaction equation
[OH:1][C:2]1[C:11]2[C:6](=[CH:7][CH:8]=[C:9]([O:12][CH3:13])[CH:10]=2)[CH:5]=[CH:4][C:3]=1[C:14]([OH:16])=[O:15].B(F)(F)F.[CH3:21]COCC>CO>[OH:1][C:2]1[C:11]2[C:6](=[CH:7][CH:8]=[C:9]([O:12][CH3:13])[CH:10]=2)[CH:5]=[CH:4][C:3]=1[C:14]([O:16][CH3:21])=[O:15]

Participants

4

Reactant 2

HCID 8000Boron trifluoride etherateHCID 142567491-Hydroxy-7-methoxynaphthalene-2-carboxylic acid

Product 1

HCID 13404481Methyl 1-hydroxy-7-methoxynaphthalene-2-carboxylateYield 92.3%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A suspension of 6.2 g (0.028 mole) of 1-hydroxy-7-methoxy-2-naphthalenecarboxylic acid in 75 ml of methanol under a nitrogen atmosphere was treated over 15 minutes with 15.0 ml (17.3 g; 0.12 mole) of boron trifluoride etherate. The mixture was stirred at reflux for 45 hours, cooled, and added slowly to 500 ml of ice cold 5% aqueous sodium bicarbonate solution. The precipitated product was filtered, and washed with water to yield 6.0 g (92% yield) of the ester, mp 80°-83°, suitable for further synthetic use. A sample purified by chromatography (silica gel, dichloromethane elution) was analytically pure, mp 79°-81° (a mp of 81°-82° is given by M. E. Alonso, A. W. Chitty, S. Pekerar, and M. de L. Borgo, J. Chem. Soc. Chem. Comm., 1542 (1984).

Workup

  1. temperatureat reflux for 45 hours
  2. temperaturecooled
  3. filtrationThe precipitated product was filtered
  4. washwashed with water

Sources & evidence

ORD record
ord-d4f8c9d85c0c423a9f6818950109a79c
Source dataset
uspto-grants-1988_08
Patent number
US04767776

Reaction notes

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