Methyl chloroformate → Methyl [1-(3-nitrophenyl)propan-2-yl]carbamate

5.33 ml of methyl chloroformate were added dropwise to a mixture consisting of 12.6 gm of 1-(3'-nitro-phenyl)-2-amino-propane, 9.8 gm of potassium carbonate and 100 ml of acetonitrile, whereby the temperature of the mixture rose to 45° C, and the resulting mixture was boiled for 2 hours. Thereafter, the reaction mixture was diluted with ice water, and the crystals precipitated thereby were collected by suction filtration, washed with water and dried, yielding 11 gm of 1-(3'-nitro-phenyl)-2-(methoxycarbonyl-amino)-propane, m.p. 104° -105° C. This compound was hydrogenated in methanol in the presence of Raney nickel at atmospheric pressure and room temperature. Thereafter, the catalyst was removed by suction filtration, the methanol was distilled out of the filtrate, and the residue, 1-(3'-amino-phenyl)-2-(methoxycarbonyl-amino)-propane, was dissolved in acetonitrile. The resulting solution was admixed with the calculated amount of maleic acid, and the precipitate formed thereby was recrystallized twice from acetonitrile, yielding 5.5 gm of the maleate of the formula ##STR29## which had a melting point of 125° -127° C.