diethyl 2-aminopropanedioate

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: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:; See reaction.notes.procedure_details.

Procedure: To a solution of sodium ethoxide (5.14 g) in absolute ethanol (75 mL) at 0° C. under a nitrogen atmosphere, a solution of diethyl aminomalonate (hydrochloride salt, 8 g) in absolute ethanol (75 mL) was slowly added. A yellow suspension was obtained at the end of the addition. 1,3-dibromo propane (7.7 mL) was then added and the resulting mixture was stirred at reflux temperature for 5 hours. The mixture was allowed to cool down to rt, then ethanol was removed in vacuo to give a yellow solid. This was dissolved in HCl (1M solution, 20 mL) and then washed with ethyl ether (2×50 mL). Phases were separated and the aqueous phase was brought to pH=9 by adding NaOH (1M solution). It was then extracted with ethyl ether (3×50 mL) and washed with brine (20 mL). The organic phase was dried and concentrated in vacuo to give the desired compound (2.35 g) as yellow oil. A yellow suspension was obtained at the end of the addition at reflux temperature for 5 hours ethanol was removed in vacuo to give a yellow solid washed with ethyl ether (2×50 mL) Phases were separated by adding NaOH (1M solution) It was then extracted with ethyl ether (3×50 mL) washed with brine (20 mL) The organic phase was dried concentrated in vacuo

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

Procedure: Diethyl aminomalonate (21.1 g, 0.1 mol) was dissolved in ethanol and sodium ethoxide in ethanol (50 mL of 1 M) was added. Propionaldehyde (6.6 g, 0.11 mol) and sodium cyanoborohydride (3.6 g, 0.058 mol) were added to the stirred solution. After 30 minutes additional propionaldehyde (6.0 g) and sodium cyanoborohydride (2.6 g) were added to complete the reaction. The solution was evaporated, and the residue was partitioned between ethyl acetate and water. Evaporation of the ethyl acetate gave 25.1 g of diethyl (propylamino)malonate. This was mixed with di t-butyl dicarbonate (34 g, 0.156 mol) and the mixture was heated at 100° C. for 1 hour. The crude product was chromatographed on silica gel using ethyl acetate:hexane as the eluant to give 21.2 g of diethyl (N-(1,1-dimethylethoxycarbonyl)propylamino)malonate as an oil. the reaction The solution was evaporated the residue was partitioned between ethyl acetate and water Evaporation of the ethyl acetate

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