Ammonium → 5-Chloro-2-nitroaniline

Compounds of formula I can be prepared without using the intermediate of formula II. For example, 3,4-dinitrochlorobenzene may be treated with liquid ammonium in a solvent such as ethanol to obtain 2-nitro-5-chloroaniline, which may then be treated with acetic anhydride in a solvent such as pyridine at 0°-5° C. to yield 2-nitro-5-chloroacetanilide. The 2-nitro-5-chloro acetanilide may then be converted to the corresponding 2-dialkylamino-5-chloroacetanilide by hydrogenating the nitro compound using platinum on carbon as catalyst in the presence of an aliphatic aldehyde (2:1 molar ratio to the nitro compound). The acetanilide can be hydrolyzed with a reagent such as sodium methoxide in a solvent such as methanol to give the corresponding 2-dialkylamino-5-chloroaniline. The chloroaniline can be treated with an appropriate reagent to give a 2-dialkylamino-5-substituted-aniline, e.g. the chloroaniline reacted with 1-propanethiol and sodium hydroxide in dimethylformamide/water at room temperature will yield 2-dialkylamino-5-propylthioaniline. This aniline may then be treated as the compound of formula III on page 5 to obtain a compound of formula I.