Green preparation process of n-(4-ethoxycarbonylphenyl)-n'-methyl-n'-phenylformamidine intermediates

Abstract

The invention discloses an environment-friendly preparation process of an N-(4-ethoxy carbonyl phenyl)-N'-methyl-N'-phenyl formamidine intermediate. The process comprises the steps of making p-nitrobenzoic acid and ethyl alcohol be subjected to an esterification reaction under the catalysis of concentrated sulphuric acid, conducting aftertreatment and catalytic hydrogenation on materials generated after the esterification reaction, and obtaining ethyl p-aminobenzoate; an aftertreatment procedure comprises the steps of removing ethyl alcohol in the materials generated after the esterification reaction through evaporation, then leaving remaining materials standing still for layering, and conducting neutralization treatment on materials on the lower layer. According to the environment-friendly preparation process, the concentrated sulfuric acid is separated out before neutralization treatment is conducted on the materials obtained after the esterification reaction, a great amount of high salinity waste water cannot be generated, environment pollution is reduced, and the yield of the esterification reaction can be raised.

Description

technical field [0001] The invention belongs to the technical field of fine chemicals, and specifically relates to a green preparation process of N-(4-ethoxycarbonylphenyl)-N'-methyl-N'-phenylformamidine intermediate ethyl p-aminobenzoate . Background technique [0002] N-(4-ethoxycarbonylphenyl)-N'-methyl-N'-phenylformamidine is a highly efficient anti-ultraviolet additive, which can efficiently absorb ultraviolet light in the 240-340nm band. N-(4-ethoxycarbonylphenyl)-N'-methyl-N'-phenylformamidine has good compatibility with organic macromolecules, and has good light and heat stability, and is widely used in polyurethane, Adhesives, foams and other polymer materials. N-(4-ethoxycarbonylphenyl)-N'-methyl-N'-phenylformamidine is liquid at room temperature, has good processability, and is compatible with ultraviolet light of benzophenone or benzotriazole Compared with absorbents, N-(4-ethoxycarbonylphenyl)-N'-methyl-N'-phenylformamidine has better anti-ultraviolet perform...

AI Technical Summary

Problems solved by technology

However, the concentrated sulfuric acid used in the prior art is commercially available pure concentrated sulfuric acid, so that the cost is relatively high, and the concentrated sulfuric acid directly enters the acid-base neutralization process after the esterification reaction, which will not only produce a large amount of high-salt wastewater, but also cause environmental damage. Larger pollution, but also cause the hydrolysis of ethyl p-nitrobenzoate, resulting in a reduction in the yield of esterification