tert-butyl N-[(2S)-1-hydroxypropan-2-yl]-N-methylcarbamate

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 18.0 g Boc-N-methyl-alaninol (95 mmol) in 95 ml dichloromethane was added a solution of 3.2 g NaHCO3 (38 mmol) and 1.14 g KBr (9.5 mmol) in 95 ml deionized water. The reaction mixture was cooled to 0° C. and after the addition of 152 mg 2,2,6,6-tetramethyl-piperidin-1-oxyl (TEMPO, 0.95 mmol), 72 g 10.3% aqueous sodium hypochlorite (105 mmol Cl2) were added under stirring over 2.5 h at 0-5°. After additional stirring for 30 min the excess of NaOCl was destroyed by the addition 38% aqueous sodium bisulfite (1 ml) and the reaction mixture was warmed up to 20°. The aqueous layer was extracted with 100 ml dichloromethane and the organic layers were washed with 100 ml 10% brine and dried (Na2SO4). Removal of the solvent by rotary evaporation afforded 14.4 g (80%) crude product as a light orange oil, [α]D=−82 (CHCl3; c=1). 1H-NMR: were added was destroyed by the addition 38% aqueous sodium bisulfite (1 ml) the reaction mixture was warmed up to 20° The aqueous layer was extracted with 100 ml dichloromethane the organic layers were washed with 100 ml 10% brine dried (Na2SO4) Removal of the solvent by rotary evaporation

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 20.3 g Boc-MeAla-OH (100 mmol; Fluka) were dissolved in 80 ml THF and cooled to 0° C. 150 ml 1M BH3-THF (150 mmol; Fluka) were added at 0° C. over 1 h and after additional stirring at 0° C. for 1 h, 65 ml deionized water were added carefully at 0-5° C. After warming up to RT 160 ml 10% Na2CO3 were added and stirring continued for 1 h. The reaction mixture was extracted with 500 ml and 400 ml ethyl acetate and the organic layers were washed with brine and dried (Na2SO4). Removal of the solvent by rotary evaporation gave 18.5 g (98%) product as a colorless oil, [α]D=−6.1 (CHCl3; c=1). 1H-NMR: were added carefully at 0-5° C were added stirring continued for 1 h The reaction mixture was extracted with 500 ml and 400 ml ethyl acetate the organic layers were washed with brine dried (Na2SO4) Removal of the solvent by rotary evaporation

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 20.3 g Boc-MeAla-OH (100 mmol; Fluka) were dissolved in 80 ml THF and cooled to 0° C. 150 ml 1M BH3-THF (150 mmol; Fluka) were added at 0° C. over 1 h and after additional stirring at 0° C. for 1 h, 65 ml deionized water were added carefully at 0-5° C. After warming up to RT 160 ml 10% Na2CO3 were added and stirring continued for 1 h. The reaction mixture was extracted with 500 ml and 400 ml ethyl acetate and the organic layers were washed with brine and dried (Na2SO4). Removal of the solvent by rotary evaporation gave 18.5 g (98%) product as a colorless oil, [α]D=−6.1 (CHCl3; c=1). 1H-NMR: were added carefully at 0-5° C were added stirring continued for 1 h The reaction mixture was extracted with 500 ml and 400 ml ethyl acetate the organic layers were washed with brine dried (Na2SO4) Removal of the solvent by rotary evaporation

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 18.0 g Boc-N-methyl-alaninol (95 mmol) in 95 ml dichloromethane was added a solution of 3.2 g NaHCO3 (38 mmol) and 1.14 g KBr (9.5 mmol) in 95 ml deionized water. The reaction mixture was cooled to 0° C. and after the addition of 152 mg 2,2,6,6-tetramethyl-piperidin-1-oxyl (TEMPO, 0.95 mmol), 72 g 10.3% aqueous sodium hypochlorite (105 mmol Cl2) were added under stirring over 2.5 h at 0-5°. After additional stirring for 30 min the excess of NaOCl was destroyed by the addition 38% aqueous sodium bisulfite (1 ml) and the reaction mixture was warmed up to 20°. The aqueous layer was extracted with 100 ml dichloromethane and the organic layers were washed with 100 ml 10% brine and dried (Na2SO4). Removal of the solvent by rotary evaporation afforded 14.4 g (80%) crude product as a light orange oil, [α]D=−82 (CHCl3; c=1). 1H-NMR: were added was destroyed by the addition 38% aqueous sodium bisulfite (1 ml) the reaction mixture was warmed up to 20° The aqueous layer was extracted with 100 ml dichloromethane the organic layers were washed with 100 ml 10% brine dried (Na2SO4) Removal of the solvent by rotary evaporation

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 20.3 g Boc-MeAla-OH (100 mmol; Fluka) were dissolved in 80 ml THF and cooled to 0° C. 150 ml 1M BH3-THF (150 mmol; Fluka) were added at 0° C. over 1 h and after additional stirring at 0° C. for 1 h, 65 ml deionized water were added carefully at 0-5° C. After warming up to RT 160 ml 10% Na2CO3 were added and stirring continued for 1 h. The reaction mixture was extracted with 500 ml and 400 ml ethyl acetate and the organic layers were washed with brine and dried (Na2SO4). Removal of the solvent by rotary evaporation gave 18.5 g (98%) product as a colorless oil, [α]D=−6.1 (CHCl3; c=1). 1H-NMR: were added carefully at 0-5° C were added stirring continued for 1 h The reaction mixture was extracted with 500 ml and 400 ml ethyl acetate the organic layers were washed with brine dried (Na2SO4) Removal of the solvent by rotary evaporation