Process for preparing N,N-dimethylaminobenzoic acids
AssigneeAmerican Cyanamid Company
InventorsJohn H. Bright, Joseph L. Schmitt, Jr.
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Abstract
N,N-Dimethylaminobenzoic acids are prepared by a two-step process of reductively alkylating nitrobenzoic acid in methanol in the presence of a palladium catalyst.
Claims10
A process for the manufacture of 3-dimethylaminobenzoic acid which comprises (1) a first step of reacting a methanolic solution of one molar proportion of 3-nitro-benzoic acid with three molar proportions of hydrogen under superatmospheric pressure and at a temperature of about 10.degree.-100.degree. C. in the presence of an effective amount of palladium metal catalyst and optionally from about 0.1 to 5.0 percent by weight, based on the weight of the nitrobenzoic acid of acetic acid;
- (2) a second step of adding thereto about two molar proportions of formaldehyde and reacting the resulting mixture with an additional two molar proportions of hydrogen under superatmospheric pressure at a temperature of about 15.degree.-100.degree. C.;
- (3) filtering the resulting methanolic solution of 3-dimethylaminobenzoic acid from the catalyst and recovering 3-dimethylaminobenzoic acid therefrom.
Dependencies are inferred from the claim text.