4,5-Difluorophthalic Anhydride → 3,4-Difluorobenzoic acid

HRID 2108229Notes

Reaction equation

HRID 2108229 reaction equation
[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[O:10])[O:8]C(=O)[C:5]2=[CH:11][C:12]=1[F:13].FC1C=C(C(O)=O)C(=CC=1F)C(O)=O>CN1CCCC1=O.CC(N(C)C)=O>[F:1][C:2]1[CH:3]=[C:4]([CH:5]=[CH:11][C:12]=1[F:13])[C:9]([OH:10])=[O:8]

Participants

5

Reactant 2

HCID 6397454,5-Difluorophthalic AnhydrideHCID 6433824,5-Difluorophthalic Acid

Product 1

HCID 991663,4-Difluorobenzoic acid

Reagents, catalysts & solvents 2

HCID 13387N-methyl-2-pyrrolidoneSolventHCID 31374DimethylacetamideSolvent

Procedure

We have found that 4,5-difluorophthalic anhydride and 4,5-difluorophthalic acid may be decarboxylated in high yield to 3,4-difluorobenzoic acid in N-methyl-2-pyrrolidone or dimethyl acetamide using copper, copper oxide, copper salts, or halides and salts of Zn, Cd, Ag and Ni as a catalyst.

Sources & evidence

ORD record
ord-5ca0015295c342208e748099287e6083
Source dataset
uspto-grants-1990_06
Patent number
US04937377

Reaction notes

Loading…