Carbon Dioxide → 2,4-Dichloro-3-(methoxycarbonyl)benzoic acid

HRID 2395558Notes

Reaction equation

HRID 2395558 reaction equation
C(NC(C)C)(C)C.C([Li])CCC.[Cl:13][C:14]1[CH:23]=[CH:22][CH:21]=[C:20]([Cl:24])[C:15]=1[C:16]([O:18][CH3:19])=[O:17].[C:25](=[O:27])=[O:26]>O1CCCC1>[Cl:13][C:14]1[C:15]([C:16]([O:18][CH3:19])=[O:17])=[C:20]([Cl:24])[CH:21]=[CH:22][C:23]=1[C:25]([OH:27])=[O:26]

Participants

6

Reactant 4

HCID 280Carbon DioxideHCID 7912DiisopropylamineHCID 599542Methyl 2,6-dichlorobenzoateHCID 178418339Butyllithium

Product 1

HCID 151328742,4-Dichloro-3-(methoxycarbonyl)benzoic acid

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
0 °C

Procedure

To a stirred solution of diisopropylamine (22 ml) in dry tetrahydrofuran (160 ml) cooled to 0° C. under an inert atmosphere was added n-butyl lithium (2.5M, 67 ml) dropwise. The solution was stirred for 30 minutes at 0° C., then added to a solution of methyl 2,6-dichlorobenzoate (26.62 g) in dry tetrahydrofuran (160 ml) cooled to -78° C. under an inert atmosphere. After 1.5 hours at this temperature the mixture was poured onto excess solid carbon dioxide and left to stand overnight. The solvent was evaporated in vacuo and the residue acidified with 2N hydrochloric acid. This was then extracted with ethyl acetate, dried over anhydrous magnesium sulphate and evaporated in vacuo to yield 2,4-dichloro-3-methoxycarbonylbenzoic acid (32.37 g) as a solid, NMR (DMSO D6) δ3.93 (3H,s), 7.70 (1H, d), 7.91 (1H,d).

Workup

  1. temperaturecooled to -78° C. under an inert atmosphere
  2. waitleft
  3. waitto stand overnight
  4. customThe solvent was evaporated in vacuo
  5. extractionThis was then extracted with ethyl acetate
  6. dry with materialdried over anhydrous magnesium sulphate
  7. customevaporated in vacuo

Sources & evidence

ORD record
ord-4b9c46e2e22c4195afc4499da924e3a5
Source dataset
uspto-grants-1996_02
Patent number
US05489570

Reaction notes

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