3 - Methyl - 4 - D Amido -5 - Methyl Anthranilate Synthesis

The starting material Methyl 4-butylamino-3-methylbenzoate was nitrated with mixing acid of sulfuric acid and nitric acid, then reduction in the presence of Fe powder to afford methyl 4-butylamino-3-methyl-5-aminobenzoate, which is a new pharmaceutical intermediate. Several factors in nitration were investigated, including the amount of substrate acid, the ratio of mixing acid, temperature, time and the final dealing methods. Meanwhile, factors in the reduction including the choice of electrolytes, temperature, time and the amount of Fe powder were studied. The conditions of the synthesis of methyl 4-butylamino-3-methyl-5-aminobenzoate were preliminarily determined, which is also applicable in industrialization.