Metanilic acid

white powder

Metanilic acid was used in the synthesis of cytocompatible sulfonated polyanilines. It was used in fabrication of novel glucose biosensor having large active surface area and excellent conductivity. It undergoes microbial desulfonation to 3-aminophenol by Pseudomonas sp. strain S-313. It can be used to produce CN3O6(1-)*Cs(1+) and dicesium salt of N-nitrometanilic acid at temperature of 25°C.

3-Aminobenzenesulfonic acid was used in the synthesis of cytocompatible sulfonated polyanilines. It was used in fabrication of novel glucose biosensor having large active surface area and excellent conductivity.

ChEBI: 3-aminobenzenesulfonic acid is an aminobenzenesulfonic acid. It is a conjugate acid of a 3-aminobenzenesulfonate.

Metanilic acid can be obtained by sulfonation of aniline sulfate with oleum and boric acid at 20 – 50 ℃. The yield is 98%. For industrial production, however, nitrobenzene is sulfonated to m-nitrobenzenesulfonic acid, which is then reduced either with iron or catalytically with hydrogen. Crude 3-aminobenzenesulfonic acid can be used directly, either as a solution or dried, to obtain 3-aminophenol by alkali fusion. It is not sufficiently pure for use in dye manufacture, however. Therefore the crude solution is acidified; after filtration the product thus obtained is of satisfactory purity.

White powder. Small colorless needles; toxic.

Water insoluble [Hawley].

Metanilic acid is an amino acid. Reacts weakly with both acids and bases.

See aniline.

Flash point data for Metanilic acid are not available, however Metanilic acid is probably combustible.

Non flammable

Crystallise the acid from water (as the hydrate), under CO2 in a semi-darkened room. The solution is photosensitive. Dry it over 90% H2SO4 in a vacuum desiccator. [Beilstein 14 H 688, 14 IV 2640.]