1-benzyl-3-ethylpiperazine

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a suspension of lithium aluminium hydride (0.87 g; 22.9 mmol) in anhydrous THF (20 ml) was added dropwise a solution of 1-benzyl-3-ethylpiperazine-2,5-dion (1.50 g; 6.46 mmol) in anhydrous THF (10 ml) under ice-cooling. After stirring at room temperature for 18 hours, a mixture of water (0.25 ml) and THF (5 ml) and 2N-aqueous sodium hydroxide solution (0.5 ml) were added dropwise sequentially under ice-cooling. The mixture was stirred at room temperature for 1 hour. After filtration of aluminium hydroxide, the filtrate was condensed under reduced pressure. To the residue were added ethyl acetate and brine to separate. The organic layer was dried over anhydrous sodium sulphate. The solvent was evaporated under reduced pressure to give 1-benzyl-3-ethylpiperazine as pale yellow oil (1.29 g; 98%). cooling were added dropwise sequentially under ice- cooling The mixture was stirred at room temperature for 1 hour After filtration of aluminium hydroxide condensed under reduced pressure to separate The organic layer was dried over anhydrous sodium sulphate The solvent was evaporated under reduced pressure

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of 2,3-dichloropyrazine (3.9 g, 27 mmol), 1-benzyl-3-ethylpiperazine (4.6 g, 22.5 mmol; from Step 1) and K2CO3 (6.2 g, 45 mmol) in DMF (10 mL) was stirred at 100° C. for 4 days. The solvent from the filtered reaction mixture was evaporated off and the residue was purified by column chromatography on silica using heptane/EtOAc (90:10) as eluent to yield 5.0 g (71%) of the title compound as a light yellow oil. HRMS m/z calcd for C17H21ClN4 (M)+ 316.1455, found 316.1448. The solvent from the filtered reaction mixture was evaporated off the residue was purified by column chromatography on silica

反応条件: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of 2,3-dichloropyrazine (3.9 g, 27 mmol), 1-benzyl-3-ethylpiperazine (4.6 g, 22.5 mmol; from Step 1) and K2CO3 (6.2 g, 45 mmol) in DMF (10 mL) was stirred at 100° C. for 4 days. The solvent from the filtered reaction mixture was evaporated off and the residue was purified by column chromatography on silica using heptane/EtOAc (90:10) as eluent to yield 5.0 g (71%) of the title compound as a light yellow oil. HRMS m/z calcd for C17H21ClN4 (M)+ 316.1455, found 316.1448. The solvent from the filtered reaction mixture was evaporated off the residue was purified by column chromatography on silica

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Benzyl bromide (38.7 g, 0.22 mol) was added in portions to an ice cold (0° C.) solution of 2-ethylpiperazine (25 g, 0.22 mol) in DMF (150 mL) with such a rate that the temperature did not exceed 20° C. The mixture was stirred for 1 h, the solvent was evaporated and the residue was partitioned between CHCl3/0.5 M HCl. The aqueous phase was made alkaline (11M NaOH) and extracted three times with CHCl3. The combined organic phases were dried (MgSO4) and concentrated. The resulting oil was purified by column chromatography on silica using CHCl3, followed by CHCl3/MeOH/NH4OH (95:5:0.3) as eluents to give 31.6 g (70%) of the title compound as a yellowish oil. Anal. (C13H20N2) H, N; C: calc, 76.42 found 75.85; H, N. did not exceed 20° C the solvent was evaporated the residue was partitioned between CHCl3/0.5 M HCl extracted three times with CHCl3 The combined organic phases were dried (MgSO4) concentrated The resulting oil was purified by column chromatography on silica

反応条件: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of 2,3-dichloropyrazine (3.9 g, 27 mmol), 1-benzyl-3-ethylpiperazine (4.6 g, 22 5 mmol; from Step 1) and K2CO3 (6.2 g, 45 mmol) in DMF (10 mL) was stirred at 100° C. for 4 days The solvent from the filtered reaction mixture was evaporated off and the residue was purified by column chromatography on silica using heptane/EtOAc (90:10) as eluent to yield 5.0 g (71%) of the title compound as a light yellow oil. HRMS m/z calcd for C17H21ClN4 (M)+ 316 1455, found 3 16.1448 from the filtered reaction mixture was evaporated off the residue was purified by column chromatography on silica

反応条件: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of 2,3-dichloropyrazine (3.9 g, 27 mmol), 1-benzyl-3-ethylpiperazine (4.6 g, 22 5 mmol; from Step 1) and K2CO3 (6.2 g, 45 mmol) in DMF (10 mL) was stirred at 100° C. for 4 days The solvent from the filtered reaction mixture was evaporated off and the residue was purified by column chromatography on silica using heptane/EtOAc (90:10) as eluent to yield 5.0 g (71%) of the title compound as a light yellow oil. HRMS m/z calcd for C17H21ClN4 (M)+ 316 1455, found 3 16.1448 from the filtered reaction mixture was evaporated off the residue was purified by column chromatography on silica

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Benzyl bromide (38.7 g, 0.22 mol) was added in portions to an ice cold (˜0° C.) solution of 2-ethylpiperazine (25 g, 0.22 mol) in DMF (150 mL) with such a rate that the temperature did not exceed 20° C. The mixture was stirred for 1 h, the solvent was evaporated and the residue was partitioned between CHCl3/0.5 M HCl. The aqueous phase was made alkaline (11M NaOH) and extracted three times with CHCl3. The combined organic phases were dried (MgSO4) and concentrated. The resulting oil was purified by column chromatography on silica using CHCl3, followed by CHCl3/MeOH/NH4OH (95:5:0.3) as eluents to give 31.6 g (70%) of the title compound as a yellowish oil. Anal. (C13H20N2) H, N; C: calc, 76.42 found 75.85; H, N. did not exceed 20° C the solvent was evaporated the residue was partitioned between CHCl3/0.5 M HCl extracted three times with CHCl3 The combined organic phases were dried (MgSO4) concentrated The resulting oil was purified by column chromatography on silica

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a suspension of lithium aluminium hydride (0.87 g; 22.9 mmol) in anhydrous THF (20 ml) was added dropwise a solution of 1-benzyl-3-ethylpiperazine-2,5-dion (1.50 g; 6.46 mmol) in anhydrous THF (10 ml) under ice-cooling. After stirring at room temperature for 18 hours, a mixture of water (0.25 ml) and THF (5 ml) and 2N-aqueous sodium hydroxide solution (0.5 ml) were added dropwise sequentially under ice-cooling. The mixture was stirred at room temperature for 1 hour. After filtration of aluminium hydroxide, the filtrate was condensed under reduced pressure. To the residue were added ethyl acetate and brine to separate. The organic layer was dried over anhydrous sodium sulphate. The solvent was evaporated under reduced pressure to give 1-benzyl-3-ethylpiperazine as pale yellow oil (1.29 g; 98%). cooling were added dropwise sequentially under ice- cooling The mixture was stirred at room temperature for 1 hour After filtration of aluminium hydroxide condensed under reduced pressure to separate The organic layer was dried over anhydrous sodium sulphate The solvent was evaporated under reduced pressure

反応条件: temp:0.00; pressure:0.00; stir: