Toluene → P-Toluic Acid

Participants

Reaction Steps

As described above, p-tolualdehyde, starting material of the present invention, is synthesized through reaction of toluene with carbon monoxide in the presence of a catalyst of HF--BF3 or HCl--AlCl3, and the resulting crude p-tolualdehyde is in a form of complex with the catalyst. After passage through the ordinary step of decomposing the complex, the crude p-tolualdehyde is purified to a purity of about 93 % by distillation. The resulting p-tolualdehyde has a sufficient quality as an industrial raw material for the ordinary reaction processes other than the process l the present invention. That is, even if the resulting p-tolualdehyde as such is autooxidized with air under pressure in a solvent of acetone or ethyl acetate in the absence of catalyst, a long induction period is required for the start of reaction, and even if the reaction is started, a sufficient reaction rate cannot be obtained. Even with a sufficient time, the per-p-toluic acid yield is low, and thus the resulting p-tolualdehyde of purity of about 99 % is not industrially preferable as the starting material for the present invention.

Provenance & Evidence