1,2-diethylpyrazolidin-4-amine

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

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

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

Procedure: To a solution of approximately 3.0 g (0.016 mole) of 4-nitro-1,2-diethyl-pyrazolidine in 100 ml of toluene was added 60 ml of anhydrous ethanol and 2 g Raney nickel (washed three times with anhydrous ethanol). The mixture was added and hydrogenated for three hours at about 30 psi. The mixture was filtered to give a light yellow solution. The solvents were evaporated at reduced pressure giving the colorless liquid, 1.95 g of the title product, b.p. 113°-115° C./40 mm. The dimaleate salt melted at 119°-120° C. The mixture was added The mixture was filtered to give a light yellow solution The solvents were evaporated at reduced pressure

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

Procedure: A solution of 4-amino-1,2-diethylpyrazolidine (1.26 g, 8.8 mmol) in anhydrous toluene (5 ml) was added to a solution of 3,5-dichlorophenyl isocyanate (1.71 g, 9.1 mmol) in dry toluene (20 ml) and the mixture stirred overnight. The precipitated solid was collected, washed with toluene and dried to give the title compound, 1.94 g. This was converted to the 1:1 maleate, mp 165°-167° C. The precipitated solid was collected washed with toluene dried

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

Procedure: A solution of 4-amino-1,2-diethylpyrazolidine (1.26 g, 8.8 mmol) in anhydrous toluene (5 ml) was added to a solution of 3,5-dichlorophenyl isocyanate (1.71 g, 9.1 mmol) in dry toluene (20 ml) and the mixture stirred overnight. The precipitated solid was collected, washed with toluene and dried to give the title compound, 1.94 g. This was converted to the 1:1 maleate, mp 165°-167° C. The precipitated solid was collected washed with toluene dried

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

Procedure: A solution of 4-amino-1,2-diethylpyrazolidine (1.26 g, 8.8 mmol) in anhydrous toluene (5 ml) was added to a solution of 3,5-dichlorophenyl isocyanate (1.71 g, 9.1 mmol) in dry toluene (20 ml) and the mixture stirred overnight. The precipitated solid was collected, washed with toluene and dried to give the title compound, 1.94 g. This was converted to the 1:1 maleate, mp 165°-167° C. The precipitated solid was collected washed with toluene dried

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

Procedure: A suspension of 2-(4-chlorophenyl)-3H-imidazo[4,5-b]pyridine-3-acetic acid (5.0 g, 0.0174 mole), 1,1'carbonyldiimidazole (2.82 g, 0.0174 mole) and dry tetrahydrofuran (100 ml) was stirred at room temperature for two hours with nitrogen bubbling through it. A solution of 4-amino-1,2-diethyl-pyrazolidine (7.5 g, 0.0522 mole) in tetrahydrofuran (6 ml) was added and the reaction mixture was stirred at room temperature overnight under nitrogen. The reaction mixture was evaporated under reduced pressure to an oil. Water (200 ml) was added, and the resulting suspension was stirred. The solid was collected by filtration, rinsed twice with water, twice with 5% potassium hydroxide solution and twice again with water. The solid was dissolved in hot isopropyl alcohol, filtered hot, and acidified with hydrogen chloride in isopropyl alcohol. Isopropyl ether was added to the cloud point, and upon cooling to room temperature, a solid precipitated. The solid was collected by filtration, rinsed with isopropyl ether, and dried under high vacuum to give 4.8 g (56%) of title compound, mp 220° C. (darkens), 228°-230° C. (melts). the reaction mixture was stirred at room temperature overnight under nitrogen The reaction mixture was evaporated under reduced pressure to an oil Water (200 ml) was added the resulting suspension was stirred The solid was collected by filtration rinsed twice with water, twice with 5% potassium hydroxide solution and twice again with water The solid was dissolved in hot isopropyl alcohol filtered hot Isopropyl ether was added to the cloud point upon cooling to room temperature a solid precipitated The solid was collected by filtration rinsed with isopropyl ether dried under high vacuum

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

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

Procedure: A suspension of 2-(4-chlorophenyl)-3H-imidazo[4,5-b]pyridine-3-acetic acid (5.0 g, 0.0174 mole), 1,1'carbonyldiimidazole (2.82 g, 0.0174 mole) and dry tetrahydrofuran (100 ml) was stirred at room temperature for two hours with nitrogen bubbling through it. A solution of 4-amino-l,2-diethyl-pyrazolidine (7.5 g, 0.0522 mole) in tetrahydrofuran (6 ml) was added and the reaction mixture was stirred at room temperature overnight under nitrogen. The reaction mixture was evaporated under reduced pressure to an oil. Water (200 ml) was added, and the resulting suspension was stirred. The solid was collected by filtration, rinsed twice with water, twice with 5% potassium hydroxide solution and twice again with water. The solid was dissolved in hot isopropyl alcohol, filtered hot, and acidified with hydrogen chloride in isopropyl alcohol. Isopropyl ether was added to the cloud point, and upon cooling to room temperature, a solid precipitated. The solid was collected by filtration, rinsed with isopropyl ether, and dried under high vacuum to give 4.8 g (56%) of title compound, mp 220° C. (darkens), 228°-230° C. (melts). the reaction mixture was stirred at room temperature overnight under nitrogen The reaction mixture was evaporated under reduced pressure to an oil Water (200 ml) was added the resulting suspension was stirred The solid was collected by filtration rinsed twice with water, twice with 5% potassium hydroxide solution and twice again with water The solid was dissolved in hot isopropyl alcohol filtered hot Isopropyl ether was added to the cloud point upon cooling to room temperature a solid precipitated The solid was collected by filtration rinsed with isopropyl ether dried under high vacuum

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

Procedure: A suspension of 2-(4-chlorophenyl)-3H-imidazo[4,5-b]pyridine-3-acetic acid (5.0 g, 0.0174 mole), 1,1'carbonyldiimidazole (2.82 g, 0.0174 mole) and dry tetrahydrofuran (100 ml) was stirred at room temperature for two hours with nitrogen bubbling through it. A solution of 4-amino-l,2-diethyl-pyrazolidine (7.5 g, 0.0522 mole) in tetrahydrofuran (6 ml) was added and the reaction mixture was stirred at room temperature overnight under nitrogen. The reaction mixture was evaporated under reduced pressure to an oil. Water (200 ml) was added, and the resulting suspension was stirred. The solid was collected by filtration, rinsed twice with water, twice with 5% potassium hydroxide solution and twice again with water. The solid was dissolved in hot isopropyl alcohol, filtered hot, and acidified with hydrogen chloride in isopropyl alcohol. Isopropyl ether was added to the cloud point, and upon cooling to room temperature, a solid precipitated. The solid was collected by filtration, rinsed with isopropyl ether, and dried under high vacuum to give 4.8 g (56%) of title compound, mp 220° C. (darkens), 228°-230° C. (melts). the reaction mixture was stirred at room temperature overnight under nitrogen The reaction mixture was evaporated under reduced pressure to an oil Water (200 ml) was added the resulting suspension was stirred The solid was collected by filtration rinsed twice with water, twice with 5% potassium hydroxide solution and twice again with water The solid was dissolved in hot isopropyl alcohol filtered hot Isopropyl ether was added to the cloud point upon cooling to room temperature a solid precipitated The solid was collected by filtration rinsed with isopropyl ether dried under high vacuum

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

Procedure: To a solution of approximately 3.0 g (0.016 mole) of 4-nitro-1,2-diethyl-pyrazolidine in 100 ml of toluene was added 60 ml of anhydrous ethanol and 2 g Raney nickel (washed three times with anhydrous ethanol). The mixture was added and hydrogenated for three hours at about 30 psi. The mixture was filtered to give a light yellow solution. The solvents were evaporated at reduced pressure giving the colorless liquid, 1.95 g of the title product, b.p. 113°-115° C./40 mm. The dimaleate salt melted at 119°-120° C. The mixture was added The mixture was filtered to give a light yellow solution The solvents were evaporated at reduced pressure

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

Procedure: A suspension of 2-(4-chlorophenyl)-3H-imidazo[4,5-b]pyridine-3-acetic acid (5.0 g, 0.0174 mole), 1,1'carbonyldiimidazole (2.82 g, 0.0174 mole) and dry tetrahydrofuran (100 ml) was stirred at room temperature for two hours with nitrogen bubbling through it. A solution of 4-amino-1,2-diethyl-pyrazolidine (7.5 g, 0.0522 mole) in tetrahydrofuran (6 ml) was added and the reaction mixture was stirred at room temperature overnight under nitrogen. The reaction mixture was evaporated under reduced pressure to an oil. Water (200 ml) was added, and the resulting suspension was stirred. The solid was collected by filtration, rinsed twice with water, twice with 5% potassium hydroxide solution and twice again with water. The solid was dissolved in hot isopropyl alcohol, filtered hot, and acidified with hydrogen chloride in isopropyl alcohol. Isopropyl ether was added to the cloud point, and upon cooling to room temperature, a solid precipitated. The solid was collected by filtration, rinsed with isopropyl ether, and dried under high vacuum to give 4.8 g (56%) of title compound, mp 220° C. (darkens), 228°-230° C. (melts). the reaction mixture was stirred at room temperature overnight under nitrogen The reaction mixture was evaporated under reduced pressure to an oil Water (200 ml) was added the resulting suspension was stirred The solid was collected by filtration rinsed twice with water, twice with 5% potassium hydroxide solution and twice again with water The solid was dissolved in hot isopropyl alcohol filtered hot Isopropyl ether was added to the cloud point upon cooling to room temperature a solid precipitated The solid was collected by filtration rinsed with isopropyl ether dried under high vacuum