methyl (2S)-2-(benzylamino)propanoate

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: L-alanine methyl ester hydrochloride (15.0 g, 107 mmol) was dissolved in N,N′-dimethylformamide (150 mL), added potassium carbonate (32.5 g, 235 mmol) and benzyl bromide (18.4 g, 107 mmol) and the mixture was stirred at 80° C. overnight. Then, the mixture was reverted to room temperature, the reaction solution was filtered through a pad of celite, extracted with ethyl acetate, washed with water and brine, dried over sodium sulfate, and concentrated in vacuo. The obtained residue was purified by silica-gel column chromatography (hexane/ethyl acetate), and the title compound (12.7 g, 61%) was obtained as a colorless oil. was reverted to room temperature the reaction solution was filtered through a pad of celite extracted with ethyl acetate washed with water and brine dried over sodium sulfate concentrated in vacuo The obtained residue was purified by silica-gel column chromatography (hexane/ethyl acetate)

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

Procedure: Prepared as in Example 12-1b from benzaldehyde and (R)-methyl 2-aminopropanoate hydrochloride. Yield 95%. MS 194 (MH+).

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

Procedure: 333 g (1.72 mmol) of N-benzylalanine methyl ester (J. Chem. Soc. 4374 (1952)) are heated under reflux overnight with 860 ml of water. Product which has deposited is filtered off with suction and the filtrate is extracted once with tert.butyl methyl ether. The aqueous solution is concentrated and the crystals obtained are dried over phosphorus pentoxide in a desiccator with the first crystal fraction. Product which has deposited is filtered off with suction the filtrate is extracted once with tert.butyl methyl ether The aqueous solution is concentrated the crystals obtained are dried over phosphorus pentoxide in a desiccator with the first crystal fraction

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

Procedure: Prepared as in Example 12-1b from benzaldehyde and (R)-methyl 2-aminopropanoate hydrochloride. Yield 95%. MS 194 (MH+).

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

Procedure: 333 g (1.72 mol) of methyl N-benzylalaninate (J. Chem. Soc. 4374 (1952)) are refluxed overnight together with 860 ml of water. Precipitated product is filtered off with suction, and the filtrate is extracted once using tert.-butyl methyl ether. The aqueous solution is concentrated, and the crystals obtained and the first crystal fraction are dried in a desiccator over phosphorus pentoxide. Precipitated product is filtered off with suction the filtrate is extracted once using tert.-butyl methyl ether The aqueous solution is concentrated the crystals obtained the first crystal fraction are dried in a desiccator over phosphorus pentoxide

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

Procedure: N,N′-dicyclohexylcarbodiimide (6.0 g, 29.0 mmol) was added to a dichloromethane (150 ml) solution of methyl N-benzyl-L-alaninate (5.20 g, 26.9 mmol) and 1-{[(benzyloxy)carbonyl]amino}cyclopropanecarboxylic acid (6.30 g, 26.7 mmol) under ice cooling and the resulting mixture was stirred overnight at room temperature. The reaction mixture was concentrated under reduced pressure and then diluted with ethyl acetate, insoluble matter was removed by filtration and then the filtrate was washed with 1 N aqueous hydrochloric acid solution and saturated brine and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure and the obtained residue was purified by silica gel column chromatography [n-hexane:ethyl acetate=1:3 (v/v)] to give the title compound (7.80 g, 71%) as a colorless oil. The reaction mixture was concentrated under reduced pressure diluted with ethyl acetate, insoluble matter was removed by filtration the filtrate was washed with 1 N aqueous hydrochloric acid solution and saturated brine dried over anhydrous sodium sulfate The solvent was evaporated under reduced pressure the obtained residue was purified by silica gel column chromatography [n-hexane:ethyl acetate=1:3 (v/v)]

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

Procedure: Prepared as in Example 12-1b from benzaldehyde and (R)-methyl 2-aminopropanoate hydrochloride. Yield 95%. MS 194 (MH+).

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

Procedure: 333 g (1.72 mmol) of N-benzylalanine methyl ester (J. Chem. Soc. 4374 (1952)) are heated under reflux overnight with 860 ml of water. Product which has deposited is filtered off with suction and the filtrate is extracted once with tert.-butyl methyl ether. The aqueous solution is concentrated and the crystals obtained are dried over phosphorus pentoxide in a desiccator with the first crystal fraction. Product which has deposited is filtered off with suction the filtrate is extracted once with tert.-butyl methyl ether The aqueous solution is concentrated the crystals obtained are dried over phosphorus pentoxide in a desiccator with the first crystal fraction

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

Procedure: 333 g (1.72 mol) of methyl N-benzylalaninate (J. Chem. Soc. 4374 (1952)) are refluxed overnight together with 860 ml of water. Precipitated product is filtered off with suction, and the filtrate is extracted once using tert.-butyl methyl ether. The aqueous solution is concentrated, and the crystals obtained and the first crystal fraction are dried in a desiccator over phosphorus pentoxide. Precipitated product is filtered off with suction the filtrate is extracted once using tert.-butyl methyl ether The aqueous solution is concentrated the crystals obtained the first crystal fraction are dried in a desiccator over phosphorus pentoxide

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

Procedure: 333 g (1.72 mmol) of N-benzylalanine methyl ester (J. Chem. Soc. 4374 (1952)) are heated under reflux overnight with 860 ml of water. Product which has deposited is filtered off with suction and the filtrate is extracted once with tert.-butyl methyl ether. The aqueous solution is concentrated and the crystals obtained are dried over phosphorus pentoxide in a desiccator with the first crystal fraction. Product which has deposited is filtered off with suction the filtrate is extracted once with tert.-butyl methyl ether The aqueous solution is concentrated the crystals obtained are dried over phosphorus pentoxide in a desiccator with the first crystal fraction

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: L-alanine methyl ester hydrochloride (15.0 g, 107 mmol) was dissolved in N,N′-dimethylformamide (150 mL), added potassium carbonate (32.5 g, 235 mmol) and benzyl bromide (18.4 g, 107 mmol) and the mixture was stirred at 80° C. overnight. Then, the mixture was reverted to room temperature, the reaction solution was filtered through a pad of celite, extracted with ethyl acetate, washed with water and brine, dried over sodium sulfate, and concentrated in vacuo. The obtained residue was purified by silica-gel column chromatography (hexane/ethyl acetate), and the title compound (12.7 g, 61%) was obtained as a colorless oil. was reverted to room temperature the reaction solution was filtered through a pad of celite extracted with ethyl acetate washed with water and brine dried over sodium sulfate concentrated in vacuo The obtained residue was purified by silica-gel column chromatography (hexane/ethyl acetate)

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

Procedure: Prepared as in Example 12-1b from benzaldehyde and (R)-methyl 2-aminopropanoate hydrochloride. Yield 95%. MS 194 (MH+).