Carbon Dioxide → 3,8-Dimethoxy-2-naphthoic acid

HRID 963993

Reaction equation

HRID 963993 reaction equation
C([Li])CCC.[CH3:6][O:7][C:8]1[C:17]2[C:12](=[CH:13][C:14]([O:18][CH3:19])=[CH:15][CH:16]=2)[CH:11]=[CH:10][CH:9]=1.CN(C)CCN(C)C.[C:28](=[O:30])=[O:29].C(=O)([O-])[O-].[Na+].[Na+]>O1CCCC1.O>[CH3:19][O:18][C:14]1[C:15]([C:28]([OH:30])=[O:29])=[CH:16][C:17]2[C:12]([CH:13]=1)=[CH:11][CH:10]=[CH:9][C:8]=2[O:7][CH3:6]

Participants

8

Reactant 5

HCID 280Carbon DioxideHCID 8037N,N,N',N'-TetramethylethylenediamineHCID 10340Sodium CarbonateHCID 2969161,6-DimethoxynaphthaleneHCID 178418339Butyllithium

Product 1

HCID 190790313,8-Dimethoxy-2-naphthoic acidYield 38.9%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Procedure

n-Butyllithium (2.5M in hexanes; 220 ml) was added dropwise at 700° C. under nitrogen to a stirred solution of 1,6-dimethoxynaphthalene (95 g) in tetrahydrofuran (1000 ml). N, N, N', N'-Tetra-methylethylenediamine (150 ml) was added and the mixture was stirred at ambient temperature for 20 hours, then cooled to -20° C. and poured onto crushed solid carbon dioxide (500 g). When effervescence had ceased, the mixture was diluted with water (1000 ml), basified by the addition of sodium carbonate (100 g), washed with ether (2×100 ml) and acidified by the addition of concentrated hydrochloric acid. The product was extracted into ethyl acetate and the extracts were washed with brine, dried over magnesium sulphate, and the solvents removed in vacuo. The residue crystallised from ethyl acetate to give a solid which was collected by filtration, dried in vacuo, and ground to give 3,8-dimethoxy-2-naphthoic acid as a cream powder (45.6 g), m.p. 151°-153° C. Concentration of the liquor yielded a second crop of 3,8-dimethoxy-2-naphthoic acid (5.4 g).

Workup

  1. temperaturecooled to -20° C.
  2. additionpoured
  3. washwashed with ether (2×100 ml)
  4. additionacidified by the addition of concentrated hydrochloric acid
  5. extractionThe product was extracted into ethyl acetate
  6. washthe extracts were washed with brine
  7. dry with materialdried over magnesium sulphate
  8. customthe solvents removed in vacuo
  9. customThe residue crystallised from ethyl acetate
  10. customto give a solid which
  11. filtrationwas collected by filtration
  12. customdried in vacuo, and ground

Sources & evidence

ORD record
ord-29e77b2a28c348dd8187f35253b1a195
Source dataset
uspto-grants-1998_06
Patent number
US05767116

Linked notes

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