(4S)-4-[(2S)-2-phenylbutyl]-4,5-dihydro-1,3-oxazol-2-amine

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

Procedure: To a stirred, cooled (0° C.) solution of (2S,4S)-2-amino-4-phenyl-hexan-1-ol (270 mg, 1.40 mmol) and sodium acetate (229 mg, 2.70 mmol) in methanol (20 ml) was added dropwise a solution of cyanogen bromide (180 mg, 1.68 mmol) in methanol (2 ml) over 10 min. The mixture was then allowed to warm to r.t. and stirring was continued for 16 h. The mixture was concentrated in vacuo and the residue was taken up in ethyl acetate and washed sequentially with saturated aqueous sodium bicarbonate solution and with saturated brine. The organic phase was dried over sodium sulphate and concentrated in vacuo. The residue was purified by chromatography (column: Isolute® Flash-NH2 from Separtis; eluent: heptane/EtOAc/MeOH) to yield a light yellow solid. MS (ISP): 219.3 ([M+H]+). The mixture was concentrated in vacuo washed sequentially with saturated aqueous sodium bicarbonate solution and with saturated brine The organic phase was dried over sodium sulphate concentrated in vacuo The residue was purified by chromatography (column: Isolute® Flash-NH2 from Separtis; eluent: heptane/EtOAc/MeOH) to yield a light yellow solid

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

Procedure: To a stirred, cooled (0° C.) solution of (2S,4S)-2-amino-4-phenyl-hexan-1-ol (270 mg, 1.40 mmol) and sodium acetate (229 mg, 2.70 mmol) in methanol (20 ml) was added dropwise a solution of cyanogen bromide (180 mg, 1.68 mmol) in methanol (2 ml) over 10 min. The mixture was then allowed to warm to r.t. and stirring was continued for 16 h. The mixture was concentrated in vacuo and the residue was taken up in ethyl acetate and washed sequentially with saturated aqueous sodium bicarbonate solution and with saturated brine. The organic phase was dried over sodium sulphate and concentrated in vacuo. The residue was purified by chromatography (column: Isolute® Flash-NH2 from Separtis; eluent: heptane/EtOAc/MeOH) to yield a light yellow solid. MS (ISP): 219.3 ([M+H]+). The mixture was concentrated in vacuo washed sequentially with saturated aqueous sodium bicarbonate solution and with saturated brine The organic phase was dried over sodium sulphate concentrated in vacuo The residue was purified by chromatography (column: Isolute® Flash-NH2 from Separtis; eluent: heptane/EtOAc/MeOH) to yield a light yellow solid

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To stirred nitric acid (9.5 ml, 65% conc.) at room temperature was added (S)-4-((S)-2-phenyl-butyl)-4,5-dihydro-oxazol-2-ylamine (1.5 g, CAS 1043495-96-0) and the mixture was then heated at 60° C. for 3 hours. The mixture was then cooled in an ice-bath before being made basic by careful addition of 30% aq. sodium hydroxide solution. The resulting mixture was diluted with ethyl acetate/THF (1:1) and the phases were separated. The organic phase was washed with saturated brine, dried over sodium sulphate and concentrated in vacuo to give (S)-4-[(S)-2-(4-nitro-phenyl)-butyl]-4,5-dihydro-oxazol-2-ylamine (1.89 g, quant.) as a yellow solid. MS (ISP): 264.2 ([M+H]+). The mixture was then cooled in an ice-bath the phases were separated The organic phase was washed with saturated brine dried over sodium sulphate concentrated in vacuo