tert-butyl N-(2-methyl-3-oxobutan-2-yl)carbamate

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

Procedure: To a solution of tert-butyl 2-methyl-3-oxobutan-2-ylcarbamate (2.36 g, 11.73 mmol) in MeOH (30 mL) at 0° C. was added portion wise NaBH4 (0.887 g, 23.45 mmol). Cold bath was removed and the reaction was stirred for 1 hour. HCl solution (1 M, 0.2 mL) was then added cautiously to quench the reaction. The reaction mixture was then concentrated and diluted with EtOAc (50 mL) and water (10 mL). The phases were separated and the aqueous layer was extracted with EtOAc (2×20 mL). The combined organics were then dried (Na2SO4) and concentrated under reduced pressure. The residue was purified via silica gel flash chromatography (10-50% EtOAc-Hexanes) to afford the desired product as a white solid (2.12 g). LCMS m/z 204.1 (M+H)+, Rt 0.69 min. Cold bath was removed HCl solution (1 M, 0.2 mL) was then added cautiously to quench the reaction The reaction mixture was then concentrated diluted with EtOAc (50 mL) and water (10 mL) The phases were separated the aqueous layer was extracted with EtOAc (2×20 mL) The combined organics were then dried (Na2SO4) concentrated under reduced pressure The residue was purified via silica gel flash chromatography (10-50% EtOAc-Hexanes)

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

Procedure: To a solution of tert-butyl 1-(methoxy(methyl)amino)-2-methyl-1-oxopropan-2-ylcarbamate (4.26 g, 17.30 mmol) in THF (100 mL) at −70° C. was added drop wise methyl lithium (32.4 mL, 51.9 mmol). Cold bath was replaced with −40° C. bath and the reaction was stirred for 4 hours. Saturated NH4Cl solution (10 mL) was then added cautiously to quench the reaction. The reaction mixture was then allowed to warm to room temperature, and diluted with EtOAc (100 mL) and water (50 mL). The phases were separated and the aqueous layer was extracted with EtOAc (2×100 mL). The combined organics were then dried (Na2SO4) and concentrated under reduced pressure. The residue was purified via silica gel flash chromatography (10-50% EtOAc-Hexanes) to afford the desired product as a white solid (2.36 g). LCMS m/z 224.2 (M+Na)+, Rt 0.7 min. was replaced with −40° C. to quench the reaction The phases were separated the aqueous layer was extracted with EtOAc (2×100 mL) The combined organics were then dried (Na2SO4) concentrated under reduced pressure The residue was purified via silica gel flash chromatography (10-50% EtOAc-Hexanes)