[(1R)-1-amino-2-methylpropyl]phosphonic acid

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

Procedure: A slurry of (1R)-(+)-(1-amino-2-methylpropyl)phosphonic acid (2.57 g, 16.8 mmol), NaHCO3 (2.82 g, 33.6 mmol), and Na2CO3 (3.58 g, 33.8 mmol) in 16 mL of 2N NaOH and 3 mL of H2O was cooled in an ice water bath. To this was added benzyloxycarbonyl chloride (2.4 mL, 16.8 mmol). During the next 2 hours, two additional aliquots of benzyloxycarbonyl chloride were added (2.4 mL each). After stirring at ambient temperature for 16 hours, 40 mL of 2N NaOH was added and the mixture was partitioned between water and ether. The aqueous portion was washed with ether, acidified to pH 2 with concentrated HCl, and extracted with ethyl acetate (2×) and with methylene chloride (2×). The combined organic extracts were washed with saturated NaCl, dried over MgSO4, filtered, and concentrated in vacuo to give 4.41 g (91%) of (1R)-(+)-(1-benzyloxycarbonylamino-2-methylpropyl)phosphonic acid as a white foam. the mixture was partitioned between water and ether The aqueous portion was washed with ether extracted with ethyl acetate (2×) and with methylene chloride (2×) The combined organic extracts were washed with saturated NaCl dried over MgSO4 filtered concentrated in vacuo

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

Procedure: A slurry of (1R)-(+)-(1-amino-2-methylpropyl)phosphonic acid (2.57 g, 16.8 mmol), NaHCO3 (2.82 g, 33.6 mmol), and Na2CO3 (3.58 g, 33.8 mmol) in 16 mL of 2N NaOH and 3 mL of H2O was cooled in an ice water bath. To this was added benzyloxycarbonyl chloride (2.4 mL, 16.8 mmol). During the next 2 hours, two additional aliquots of benzyloxycarbonyl chloride were added (2.4 mL each). After stirring at ambient temperature for 16 hours, 40 mL of 2N NaOH was added and the mixture was partitioned between water and ether. The aqueous portion was washed with ether, acidified to pH 2 with concentrated HCl, and extracted with ethyl acetate (2×) and with methylene chloride (2×). The combined organic extracts were washed with saturated NaCl, dried over MgSO4, filtered, and concentrated in vacuo to give 4.41 g (91%) of (1R)-(+)-(1-benzyloxycarbonylamino-2-methylpropyl)phosphonic acid as a white foam. the mixture was partitioned between water and ether The aqueous portion was washed with ether extracted with ethyl acetate (2×) and with methylene chloride (2×) The combined organic extracts were washed with saturated NaCl dried over MgSO4 filtered concentrated in vacuo

Conditions: temp:22.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 250 mg (1.6 mmol) of (R)-(1-amino-2-methylpropyl)phosphonic acid were dissolved in 6 ml of a 1 M NaOH and 6 ml of tetrahydrofuran. 560 mg (1.96 mmol) of 4-chlorobiphenyl-4′-sulfonyl chloride were then added and the mixture was stirred at 22° C. overnight. The reaction mixture was concentrated, acidified with 2 M HCl and extracted with ethyl acetate. The 4-chlorobiphenyl4′-sulfonic acid resulting as a by-product precipitated and was separated off. After drying and concentrating the ethyl acetate phase, a solid was obtained. The reaction mixture was concentrated extracted with ethyl acetate The 4-chlorobiphenyl4′-sulfonic acid resulting as a by-product precipitated was separated off After drying concentrating the ethyl acetate phase a solid was obtained

Conditions: temp:22.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 250 mg (1.6 mmol) of (R)-(1-amino-2-methylpropyl)phosphonic acid were dissolved in 6 ml of a 1 M NaOH and 6 ml of tetrahydrofuran. 560 mg (1.96 mmol) of 4-chlorobiphenyl-4′-sulfonyl chloride were then added and the mixture was stirred at 22° C. overnight. The reaction mixture was concentrated, acidified with 2 M HCl and extracted with ethyl acetate. The 4-chlorobiphenyl4′-sulfonic acid resulting as a by-product precipitated and was separated off. After drying and concentrating the ethyl acetate phase, a solid was obtained. The reaction mixture was concentrated extracted with ethyl acetate The 4-chlorobiphenyl4′-sulfonic acid resulting as a by-product precipitated was separated off After drying concentrating the ethyl acetate phase a solid was obtained

Conditions: temp:22.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 250 mg (1.6 mmol) of (R)-(1-amino-2-methylpropyl)phosphonic acid were dissolved in 6 ml of a 1 M NaOH and 6 ml of tetrahydrofuran. 560 mg (1.96 mmol) of 4-chlorobiphenyl-4′-sulfonyl chloride were then added and the mixture was stirred at 22° C. overnight. The reaction mixture was concentrated, acidified with 2 M HCl and extracted with ethyl acetate. The 4-chlorobiphenyl4′-sulfonic acid resulting as a by-product precipitated and was separated off. After drying and concentrating the ethyl acetate phase, a solid was obtained. The reaction mixture was concentrated extracted with ethyl acetate The 4-chlorobiphenyl4′-sulfonic acid resulting as a by-product precipitated was separated off After drying concentrating the ethyl acetate phase a solid was obtained

Conditions: temp:22.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 250 mg (1.6 mmol) of (R)-(1-amino-2-methylpropyl)phosphonic acid were dissolved in 6 ml of a 1 M NaOH and 6 ml of tetrahydrofuran. 560 mg (1.96 mmol) of 4-chlorobiphenyl-4′-sulfonyl chloride were then added and the mixture was stirred at 22° C. overnight. The reaction mixture was concentrated, acidified with 2 M HCl and extracted with ethyl acetate. The 4-chlorobiphenyl-4′-sulfonic acid resulting as a by-product precipitated and was separated off. After drying and concentrating the ethyl acetate phase, a solid was obtained. The reaction mixture was concentrated extracted with ethyl acetate The 4-chlorobiphenyl-4′-sulfonic acid resulting as a by-product precipitated was separated off After drying concentrating the ethyl acetate phase a solid was obtained

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

Procedure: A slurry of (1R)-(+)-(1-amino-2-methylpropyl)phosphonic acid (2.57 g, 16.8 mmol), NaHCO3 (2.82 g, 33.6 mmol), and Na2CO3 (3.58 g, 33.8 mmol) in 16 mL of 2N NaOH and 3 mL of H2O was cooled in an ice water bath. To this was added benzyloxycarbonyl chloride (2.4 mL, 16.8 mmol). During the next 2 hours, two additional aliquots of benzyloxycarbonyl chloride were added (2.4 mL each). After stirring at ambient temperature for 16 hours, 40 mL of 2N NaOH was added and the mixture was partitioned between water and ether. The aqueous portion was washed with ether, acidified to pH 2 with concentrated HCl, and extracted with ethyl acetate (2×) and with methylene chloride (2×). The combined organic extracts were washed with saturated NaCl, dried over MgSO4, filtered, and concentrated in vacuo to give 4.41 g (91%) of (1R)-(+)-(1-benzyloxycarbonylamino-2-methylpropyl)phosphonic acid as a white foam. the mixture was partitioned between water and ether The aqueous portion was washed with ether extracted with ethyl acetate (2×) and with methylene chloride (2×) The combined organic extracts were washed with saturated NaCl dried over MgSO4 filtered concentrated in vacuo

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

Procedure: A slurry of (1R)-(+)-(1-amino-2-methylpropyl)phosphonic acid (2.57 g, 16.8 mmol), NaHCO3 (2.82 g, 33.6 mmol), and Na2CO3 (3.58 g, 33.8 mmol) in 16 mL of 2N NaOH and 3 mL of H2O was cooled in an ice water bath. To this was added benzyloxycarbonyl chloride (2.4 mL, 16.8 mmol). During the next 2 hours, two additional aliquots of benzyloxycarbonyl chloride were added (2.4 mL each). After stirring at ambient temperature for 16 hours, 40 mL of 2N NaOH was added and the mixture was partitioned between water and ether. The aqueous portion was washed with ether, acidified to pH 2 with concentrated HCl, and extracted with ethyl acetate (2×) and with methylene chloride (2×). The combined organic extracts were washed with saturated NaCl, dried over MgSO4, filtered, and concentrated in vacuo to give 4.41 g (91%) of (1R)-(+)-(1-benzyloxycarbonylamino-2-methylpropyl)phosphonic acid as a white foam. the mixture was partitioned between water and ether The aqueous portion was washed with ether extracted with ethyl acetate (2×) and with methylene chloride (2×) The combined organic extracts were washed with saturated NaCl dried over MgSO4 filtered concentrated in vacuo