(2R)-3-(benzylamino)-1,1,1-trifluoropropan-2-ol

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

Procedure: To a solution of (R)-3-(benzylamino)-1,1,1-trifluoropropan-2-ol (4-2, 5 g, 22.81 mmol) in CH3CN (200 ml) was added DIEA (12 ml, 68.7 mmol), (S)-2-chloropropionic acid (2.4 ml, 27.4 mmol), then 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide (16.3 ml, 27.4 mmol) slowly at rt. After 2.5 hr the mixture was concentrated. The material was taken up in EtOAc and washed with saturated NaHCO3, H2O, and brine. The organic layer was filtered through a pad of silica gel washing with ethyl acetate then concentrated to afford (S)—N-benzyl-2-hydroxy-N—((R)-3,3,3-trifluoro-2-hydroxypropyl)propanamide (4-3) as a clear oil which was sufficiently pure for use in the next step. slowly at rt After 2.5 hr the mixture was concentrated washed with saturated NaHCO3, H2O, and brine The organic layer was filtered through a pad of silica gel washing with ethyl acetate then concentrated

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

Procedure: To a solution of lithium trifluoromethanesulfonate (1.43 g, 9.17 mmol) in CH3CN (30 ml) was added (R)-(+)-3,3,3-trifluoro-1,2-epoxypropane (10.77 g, 96 mmol) slowly at −10° C. After 5 minutes benzylamine (10 ml, 92 mmol) was added slowly. The mixture was allowed to warm as the bath warmed to rt overnight. The mixture was concentrated. The crude product was subjected to silica gel chromatography (330 g, 0-50% EtOAc/hexanes, 10 minute gradient) to afford (R)-3-(benzylamino)-1,1,1-trifluoropropan-2-ol (4-2, 15.9 g, 79%) as a white solid. LRMS m/z (M+H)+ 220.2 calc. 220.1 found. to warm as the bath The mixture was concentrated was subjected to silica gel chromatography (330 g, 0-50% EtOAc/hexanes, 10 minute gradient)

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

Procedure: To a solution of lithium trifluoromethanesulfonate (1.43 g, 9.17 mmol) in CH3CN (30 ml) was added (R)-(+)-3,3,3-trifluoro-1,2-epoxypropane (10.77 g, 96 mmol) slowly at −10° C. After 5 minutes benzylamine (10 ml, 92 mmol) was added slowly. The mixture was allowed to warm as the bath warmed to rt overnight. The mixture was concentrated. The crude product was subjected to silica gel chromatography (330 g, 0-50% EtOAc/hexanes, 10 minute gradient) to afford (R)-3-(benzylamino)-1,1,1-trifluoropropan-2-ol (4-2, 15.9 g, 79%) as a white solid. LRMS m/z (M+H)+ 220.2 calc. 220.1 found. to warm as the bath The mixture was concentrated was subjected to silica gel chromatography (330 g, 0-50% EtOAc/hexanes, 10 minute gradient)

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

Procedure: To a solution of (R)-3-(benzylamino)-1,1,1-trifluoropropan-2-ol (4-2, 5 g, 22.81 mmol) in CH3CN (200 ml) was added DIEA (12 ml, 68.7 mmol), (S)-2-chloropropionic acid (2.4 ml, 27.4 mmol), then 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide (16.3 ml, 27.4 mmol) slowly at rt. After 2.5 hr the mixture was concentrated. The material was taken up in EtOAc and washed with saturated NaHCO3, H2O, and brine. The organic layer was filtered through a pad of silica gel washing with ethyl acetate then concentrated to afford (S)—N-benzyl-2-hydroxy-N—((R)-3,3,3-trifluoro-2-hydroxypropyl)propanamide (4-3) as a clear oil which was sufficiently pure for use in the next step. slowly at rt After 2.5 hr the mixture was concentrated washed with saturated NaHCO3, H2O, and brine The organic layer was filtered through a pad of silica gel washing with ethyl acetate then concentrated

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

Procedure: To a solution of lithium trifluoromethanesulfonate (1.43 g, 9.17 mmol) in CH3CN (30 ml) was added (R)-(+)-3,3,3-trifluoro-1,2-epoxypropane (10.77 g, 96 mmol) slowly at −10° C. After 5 minutes benzylamine (10 ml, 92 mmol) was added slowly. The mixture was allowed to warm as the bath warmed to rt overnight. The mixture was concentrated. The crude product was subjected to silica gel chromatography (330 g, 0-50% EtOAc/hexanes, 10 minute gradient) to afford (R)-3-(benzylamino)-1,1,1-trifluoropropan-2-ol (4-2, 15.9 g, 79%) as a white solid. LRMS m/z (M+H)+ 220.2 calc. 220.1 found. to warm as the bath The mixture was concentrated was subjected to silica gel chromatography (330 g, 0-50% EtOAc/hexanes, 10 minute gradient)