2,3,4-trichloroaniline

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2,3,4-Trichloroaniline (100 g) was dissolved with stirring in glacial acetic acid (875 ml) at 55°-60° C. A solution of sodium nitrite (39.5 g) in concentrated sulphuric acid (300 ml) was then added over 15 minutes at 55°-60° C. to the solution thus obtained. The viscous mixture obtained was cooled to 5°-10° C. and a solution of stannous chloride dihydrate (437 g) in concentrated hydrochloric acid (375 ml) was added at 5°-10° C. over 20 minutes. A fine, off-white solid precipitated. To aid filtration, the mixture was warmed to 60° C., allowed to cool to laboratory temperature and then filtered. The precipitate was washed on the filter with saturated aqueous sodium chloride solution (100 ml). The damp powder thus obtained was added to a stirred mixture of aqueous ammonia (1.3 liters; S.G. 0.880) and ice. The fine slurry which formed was filtered and the precipitate obtained was dried at 80° C., and boiled twice with chloroform (2×1.5 liters). The chloroform extracts were combined and evaporated to dryness to give 2,3,4-trichlorophenylhydrazine (86 g), m.p. 142°-143° C., in the form of a colourless powder. thus obtained The viscous mixture obtained was cooled to 5°-10° C. A fine, off-white solid precipitated filtration to cool to laboratory temperature filtered The precipitate was washed on the filter with saturated aqueous sodium chloride solution (100 ml) The damp powder thus obtained The fine slurry which formed was filtered the precipitate obtained was dried at 80° C. evaporated to dryness

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2,3,4-Trichloroaniline (100 g) was dissolved with stirring in glacial acetic acid (875 ml) at 55°-60° C. A solution of sodium nitrite (39.5 g) in concentrated sulphuric acid (300 ml) was then added over 15 minutes at 55°-60° C. to the solution thus obtained. The viscous mixture obtained was cooled to 5°-10° C. and a solution of stannous chloride dihydrate (437 g) in concentrated hydrochloric acid (375 ml) was added at 5°-10° C. over 20 minutes. A fine, off-white solid precipitated. To aid filtration, the mixture was warmed to 60° C., allowed to cool to laboratory temperature and then filtered. The precipitate was washed on the filter with saturated aqueous sodium chloride solution (100 ml). The damp powder thus obtained was added to a stirred mixture of aqueous ammonia (1.3 liters; S.G. 0.880) and ice. The fine slurry which formed was filtered and the precipitate obtained was dried at 80° C., and boiled twice with chloroform (2×1.5 liters). The chloroform extracts were combined and evaporated to dryness to give 2,3,4-trichlorophenylhydrazine (86 g), m.p. 142°-143° C., in the form of a colourless powder. thus obtained The viscous mixture obtained was cooled to 5°-10° C. A fine, off-white solid precipitated filtration to cool to laboratory temperature filtered The precipitate was washed on the filter with saturated aqueous sodium chloride solution (100 ml) The damp powder thus obtained The fine slurry which formed was filtered the precipitate obtained was dried at 80° C. evaporated to dryness

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Phthaloyl dichloride (100.0 g) was added dropwise to a mixture of aqueous sodium hydroxide solution (40.39 g/300 mL), 2-methyl-1-methylthio-2-propanamine (61.66 g) and chloroform (300 mL) at 25° C. or lower. After completion of the dropwise addition, the resulting mixture was stirred at 20° C. for 30 minutes and the organic layer was separated to prepare a solution of N-[1,1-dimethyl-2-(methylthio)ethyl]isophthalimide in 1,2-dichloroethane. The previously prepared isophthalimide solution was added dropwise to a mixture of 2,3,4-trichloroaniline (91.93 g), p-toluenesulfonic acid monohydrate (2.34 g) and chloroform (75 mL) at 60° C. and then stirred for 30 minutes. Subsequently, formic acid (2.27 g) was added thereto and then 35% hydrogen peroxide (52.66 g) was slowly dropped thereinto with heating under reflux. Thereafter, the resulting mixture was stirred at 60° C. for 3 hours. An aqueous sodium sulfite solution was added dropwise to the thus obtained reaction mixture at the same temperature to decompose the excess oxidizing agent. Then, the resulting mixture was neutralized with an aqueous sodium hydrogencarbonate solution, after which the organic layer was separated. The organic layer obtained was heated at 60° C. Heptane (800 mL) was added dropwise thereto and the resulting mixture was slowly cooled to 20° C. The crystals precipitated were filtered, washed with water and then dried to obtain 202.44 g (yield 89%) of the title compound. After completion of the dropwise addition the organic layer was separated to prepare a solution of N-[1,1-dimethyl-2-(methylthio)ethyl]isophthalimide in 1,2-dichloroethane stirred for 30 minutes with heating under reflux Thereafter, the resulting mixture was stirred at 60° C. for 3 hours after which the organic layer was separated The organic layer obtained was heated at 60° C the resulting mixture was slowly cooled to 20° C The crystals precipitated were filtered washed with water dried

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2,3,4-Trichloroaniline (100 g) was dissolved with stirring in glacial acetic acid (875 ml) at 55°-60° C. A solution of sodium nitrite (39.5 g) in concentrated sulphuric acid (300 ml) was then added over 15 minutes at 55°-60° C. to the solution thus obtained. The viscous mixture obtained was cooled to 5°-10° C. and a solution of stannous chloride dihydrate (437 g) in concentrated hydrochloric acid (375 ml) was added at 5°-10° C. over 20 minutes. A fine, off-white solid precipitated. To aid filtration, the mixture was warmed to 60° C., allowed to cool to laboratory temperature and then filtered. The precipitate was washed on the filter with saturated aqueous sodium chloride solution (100 ml). The damp powder thus obtained was added to a stirred mixture of aqueous ammonia (1.3 liters; S.G. 0.880) and ice. The fine slurry which formed was filtered and the precipitate obtained was dried at 80° C., and boiled twice with chloroform (2×1.5 liters). The chloroform extracts were combined and evaporated to dryness to give 2,3,4-trichlorophenylhydrazine (86 g), m.p. 142°-143° C., in the form of a colourless powder. thus obtained The viscous mixture obtained was cooled to 5°-10° C. A fine, off-white solid precipitated filtration to cool to laboratory temperature filtered The precipitate was washed on the filter with saturated aqueous sodium chloride solution (100 ml) The damp powder thus obtained The fine slurry which formed was filtered the precipitate obtained was dried at 80° C. evaporated to dryness

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Fifty grams of 2,3,4-trichloroaniline was added portionwise to a solution of 200 ml of concentrated hydrochloric acid at approximately 0° C. To the reaction mixture was added 17.6 g of sodium nitrite dissolved in 100 ml of water dropwise over 1 hour. Next, 94.8 g of stannous chloride dissolved in 100 ml of concentrated hydrochloric acid was added dropwise to the reaction mixture over a 1 hour period while maintaining the temperature at approximately 0° C. The reaction mixture was stirred for approximately 1 hour at this temperature and then warmed to room temperature and stirred for 20 additional hours. The precipitated solid was collected by filtration and dried. The collected solid was added to a cold solution of 300 ml of 25% aqueous sodium hydroxide and this solution was stirred at approximately 5° C. for 1 hour. This aqueous solution was then extracted with ether and the organic phase was washed with water and saturated sodium chloride, and finally dried over anhydrous magnesium sulfate. The organic phase was evaporated under reduced pressure and the residue was recrystallized from ethanol to afford 35 g of 2,3,4-trichlorophenylhydrazine. Yield 66%. mp=138°-140° C. was added dropwise to the reaction mixture over a 1 hour period warmed to room temperature stirred for 20 additional hours The precipitated solid was collected by filtration dried The collected solid was added to a cold solution of 300 ml of 25% aqueous sodium hydroxide this solution was stirred at approximately 5° C. for 1 hour This aqueous solution was then extracted with ether the organic phase was washed with water and saturated sodium chloride finally dried over anhydrous magnesium sulfate The organic phase was evaporated under reduced pressure the residue was recrystallized from ethanol