methyl 2-(2-methylpropylamino)acetate

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

Procedure: Glycine methylester hydrochloride (2.0 g, 16.0 mmol) was dissolved in MeOH/AcOH (9:1, 25 ml). Triethylamine (1.8 g, 18.0 mmol) was added followed by 2-butanone (1.3 g, 18.0 mmol). After 2 h at room temperature sodium triacetoxyborohydride (3.81 g, 18.0 mmol) was added. After 18 h at room temperature the solvent was removed in vacuo and the residue was taken up in chloroform (200 ml). This solution was washed with sat. NaHCO3, water and brine, dried (Na2SO4) and evaporated in vacuo to give a colourless oil identified as the title compound (646 mg, 4.46 mmol, 28%). After 18 h at room temperature the solvent was removed in vacuo This solution was washed with sat. NaHCO3, water and brine dried (Na2SO4) evaporated in vacuo to give a colourless oil

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

Procedure: To a suspension of 4-benzyloxyphthalic anhydride (25.42 g, 100 mmol) in methanol (200 mL) was added 28% sodium methoxide methanol solution (21.22 g, 110 mmol) and the mixture was stirred at room temperature for 1 h. The reaction mixture was poured into 1N hydrochloric acid (150 mL) and extracted with ethyl acetate. The extract was washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was dissolved in N,N-dimethylformamide (200 mL) and methyl 2-(isobutylamino)acetate (17.42 g, 120 mmol), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (23.00 g, 120 mmol) and 1-hydroxybenzotriazole (18.34 g, 120 mmol) were added, and the mixture was stirred at room temperature for 3 h. The reaction mixture was poured into water and extracted with ethyl acetate. The extract was washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was dissolved in methanol (50 mL) and a solution of 28% sodium methoxide methanol solution (38.59 g, 200 mmol) was added thereto. The mixture was stirred at room temperature for 1 h. The reaction mixture was poured into 1N hydrochloric acid (200 mL) and extracted with ethyl acetate. The extract was washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography and the component eluted earlier was concentrated to give methyl 7-benzyloxy-4-hydroxy-2-isobutyl-1-oxo-1,2-dihydro-3-isoquinolinecarboxylate (4.76 g, 12.1%) as an oil. extracted with ethyl acetate The extract was washed with brine dried over anhydrous magnesium sulfate concentrated under reduced pressure The residue was dissolved in N,N-dimethylformamide (200 mL) the mixture was stirred at room temperature for 3 h extracted with ethyl acetate The extract was washed with brine dried over anhydrous magnesium sulfate concentrated under reduced pressure The residue was dissolved in methanol (50 mL) The mixture was stirred at room temperature for 1 h extracted with ethyl acetate The extract was washed with brine dried over anhydrous magnesium sulfate concentrated under reduced pressure The residue was purified by silica gel column chromatography the component eluted earlier was concentrated