methyl 2,3-dibromopropanoate

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 solution of methyl 2,3-dibromopropionate (25 mL, 198 mmol) in toluene at 5° C. was added triethylamine (55 mL, 0.39 mmol) in toluene (100 mL). After stirring for 5 min (S)-(1)-phenethylamine (25 mL, 198 mmol) in toluene (100 mL) was added dropwise. The suspension was refluxed for 3 h and allowed to cool down, filtered and the volatiles were evaporated under reduced pressure to give a residue that was purified by column chromatography (950 g of silica gel) with a gradient of 0-20% EtOAc in cyclohexane to yield to (S)-methyl 1-((S)-1-phenylethyl)aziridine-2-carboxylate EBE 06044A as a yellow oil (17.31 g, 43% yield) and (R)-methyl 1-((S)-1-phenylethyl)aziridine-2-carboxylate EBE 06044B as a yellow oil (15.14 g, 37% yield). was added dropwise The suspension was refluxed for 3 h to cool down filtered the volatiles were evaporated under reduced pressure to give a residue that was purified by column chromatography (950 g of silica gel) with a gradient of 0-20% EtOAc in cyclohexane

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 1-phenyl-N-[(2R)-pyrrolidin-2-ylmethyl]methanamine (13.6 g) in toluene (120 mL) were added triethylamine (22.9 mL) and methyl 2,3-dibromopropanoate (13.4 g) under ice-cooling, and the mixture was stirred with heating at 90° C. for 5 hr. The reaction mixture was allowed to cool to room temperature, and diluted with diethyl ether (200 mL) and brine (200 mL). The organic layer was dried over anhydrous magnesium sulfate, and the insoluble material was filtered off. The filtrate was concentrated under reduced pressure, and purified by silica gel column chromatography (ethyl acetate/hexane=10/80→50/50) to give the title compound (6.86 g) as a pale-yellow oil. cooling to cool to room temperature The organic layer was dried over anhydrous magnesium sulfate the insoluble material was filtered off The filtrate was concentrated under reduced pressure purified by silica gel column chromatography (ethyl acetate/hexane=10/80→50/50)

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 1-phenyl-N-[(2R)-pyrrolidin-2-ylmethyl]methanamine (13.6 g) in toluene (120 mL) were added triethylamine (22.9 mL) and methyl 2,3-dibromopropanoate (13.4 g) under ice-cooling, and the mixture was stirred with heating at 90° C. for 5 hr. The reaction mixture was allowed to cool to room temperature, and diluted with diethyl ether (200 mL) and brine (200 mL). The organic layer was dried over anhydrous magnesium sulfate, and the insoluble material was filtered off. The filtrate was concentrated under reduced pressure, and purified by silica gel column chromatography (ethyl acetate/hexane=10/80→50/50) to give the title compound (6.86 g) as a pale-yellow oil. cooling to cool to room temperature The organic layer was dried over anhydrous magnesium sulfate the insoluble material was filtered off The filtrate was concentrated under reduced pressure purified by silica gel column chromatography (ethyl acetate/hexane=10/80→50/50)

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 1-phenyl-N-[(2R)-pyrrolidin-2-ylmethyl]methanamine (13.6 g) in toluene (120 mL) were added triethylamine (22.9 mL) and methyl 2,3-dibromopropanoate (13.4 g) under ice-cooling, and the mixture was stirred with heating at 90° C. for 5 hr. The reaction mixture was allowed to cool to room temperature, and diluted with diethyl ether (200 mL) and brine (200 mL). The organic layer was dried over anhydrous magnesium sulfate, and the insoluble material was filtered off. The filtrate was concentrated under reduced pressure, and purified by silica gel column chromatography (ethyl acetate/hexane=10/80→50/50) to give the title compound (6.86 g) as a pale-yellow oil. cooling to cool to room temperature The organic layer was dried over anhydrous magnesium sulfate the insoluble material was filtered off The filtrate was concentrated under reduced pressure purified by silica gel column chromatography (ethyl acetate/hexane=10/80→50/50)

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 1-phenyl-N-[(2R)-pyrrolidin-2-ylmethyl]methanamine (13.6 g) in toluene (120 mL) were added triethylamine (22.9 mL) and methyl 2,3-dibromopropanoate (13.4 g) under ice-cooling, and the mixture was stirred with heating at 90° C. for 5 hr. The reaction mixture was allowed to cool to room temperature, and diluted with diethyl ether (200 mL) and brine (200 mL). The organic layer was dried over anhydrous magnesium sulfate, and the insoluble material was filtered off. The filtrate was concentrated under reduced pressure, and purified by silica gel column chromatography (ethyl acetate/hexane=10/80→50/50) to give the title compound (6.86 g) as a pale-yellow oil. cooling to cool to room temperature The organic layer was dried over anhydrous magnesium sulfate the insoluble material was filtered off The filtrate was concentrated under reduced pressure purified by silica gel column chromatography (ethyl acetate/hexane=10/80→50/50)

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

Procedure: To solution of methyl 2,3-dibromopropionate (25 mL, 198 mmol) in toluene at 5° C. was added triethylamine (55 mL, 0.39 mmol) in toluene (100 mL). After stirring for 5 min (S)-(1)-phenethylamine (25 mL, 198 mmol) in toluene (100 mL) was added dropwise. The suspension was refluxed for 3 h and allowed to cool down, filtered and the volatiles were evaporated under reduced pressure to give a residue that was purified by column chromatography (950 g of silica gel) with a gradient of 0-20% EtOAc in cyclohexane to yield to (S)-methyl 145)-1-phenylethyl)aziridine-2-carboxylate EBE 06044A as a yellow oil (17.31 g, 43% yield) and (R)-methyl 1-((S)-1-phenylethyl)aziridine-2-carboxylate EBE 06044B as a yellow oil (15.14 g, 37% yield). was added dropwise The suspension was refluxed for 3 h to cool down filtered the volatiles were evaporated under reduced pressure to give a residue that was purified by column chromatography (950 g of silica gel) with a gradient of 0-20% EtOAc in cyclohexane

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

Procedure: Methyl 2,3-dibromopropionate (21.9 g) and trimethylamine N-oxide (0.1 g) in methanol (8 ml) were cooled to −5° C. with stirring under an atmosphere of nitrogen. A methanolic solution of sodium methoxide, freshly prepared from sodium (2.25 g) and methanol (24 ml), was added dropwise over 15 minutes to the mixture, which was maintained below 0° C. by cooling. On completion of addition, the mixture was stirred for a further 30 minutes and acetic acid (1 ml) was added followed by diethyl ether (100 ml). The mixture was filtered to remove insoluble salts and the filtrate evaporated under reduced pressure to give an oil, which was re-dissolved in a small volume of diethyl ether and re-filtered. The filtrate was evaporated under reduced pressure to give the required product (17.4 g) as a pale yellow oil. was added dropwise over 15 minutes to the mixture, which was maintained below 0° C. by cooling On completion of addition the mixture was stirred for a further 30 minutes The mixture was filtered to remove insoluble salts the filtrate evaporated under reduced pressure to give an oil, which re-filtered The filtrate was evaporated under reduced pressure

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

Procedure: Methyl 2,3-dibromopropionate (21.9 g) and trimethylamine N-oxide (0.1 g) in methanol (8 ml) were cooled to −5° C. with stirring under an atmosphere of nitrogen. A methanolic solution of sodium methoxide, freshly prepared from sodium (2.25 g) and methanol (24 ml), was added dropwise over 15 minutes to the mixture, which was maintained below 0° C. by cooling. On completion of addition, the mixture was stirred for a further 30 minutes and acetic acid (1 ml) was added followed by diethyl ether (100 ml). The mixture was filtered to remove insoluble salts and the filtrate evaporated under reduced pressure to give an oil, which was re-dissolved in a small volume of diethyl ether and re-filtered. The filtrate was evaporated under reduced pressure to give the required product (17.4 g) as a pale yellow oil. was added dropwise over 15 minutes to the mixture, which was maintained below 0° C. by cooling On completion of addition the mixture was stirred for a further 30 minutes The mixture was filtered to remove insoluble salts the filtrate evaporated under reduced pressure to give an oil, which re-filtered The filtrate was evaporated under reduced pressure