Lithium hydroxide, monohydrate → 4-Cyano-2-methylbenzoic acid

HRID 1970849Notes

Reaction equation

HRID 1970849 reaction equation
C[O:2][C:3](=[O:13])[C:4]1[CH:9]=[CH:8][C:7]([C:10]#[N:11])=[CH:6][C:5]=1[CH3:12].O.[OH-].[Li+]>O.O1CCCC1>[C:10]([C:7]1[CH:8]=[CH:9][C:4]([C:3]([OH:13])=[O:2])=[C:5]([CH3:12])[CH:6]=1)#[N:11]

Participants

5

Reactant 2

HCID 168937Lithium hydroxide, monohydrateHCID 18766060Methyl 4-cyano-2-methylbenzoate

Product 1

HCID 118193394-Cyano-2-methylbenzoic acidYield 99%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Procedure

To a solution of 4-cyano-2-methylbenzoic acid methyl ester (Example 3.6) (61 g, 348 mmol) in a mixture of water (0.360 ml) and tetrahydrofuran (1.4 l) was added lithium hydroxide hydrate (31.4 g, 748.2 mmol). The reaction mixture was stirred at ambient temperature for 3 hours. The reaction mixture was concentrated. The residue was acidified by addition of aqueous hydrochloric acid (1N) and extracted with a mixture of methanol and chloroform (5:95). The organic phase was dried over sodium sulfate and concentrated. The residue was crystallized in a mixture of ethyl acetate andcyclohexane to give 4-cyano-2-methylbenzoic acid (55.5 g, 99% yield).

Workup

  1. concentrationThe reaction mixture was concentrated
  2. additionThe residue was acidified by addition of aqueous hydrochloric acid (1N)
  3. extractionextracted with a mixture of methanol and chloroform (5:95)
  4. dry with materialThe organic phase was dried over sodium sulfate
  5. concentrationconcentrated
  6. customThe residue was crystallized in a mixture of ethyl acetate andcyclohexane

Sources & evidence

ORD record
ord-ac3f1f786ea94194ba7047f1749570d2
Source dataset
uspto-grants-2013_04
Patent number
US08431514B2

Reaction notes

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