4-Methylmorpholine → Tert-butyl 1-(aminocarbonyl)-2,2-dimethylpropylcarbamate

Temperature

-15 °C

A stirred solution of Example 22A (1.81 g, 7.83 mmol) in THF (20 mL) at−40° C. was treated with isobutyl chloroformate (1.01 mL, 7.83 mmol) followed by N-methylmorpholine (0.860 mL, 7.83 mmol). After 15 minutes, the milky white reaction mixture was treated dropwise with ammonium hydroxide (6.0 mL of 30% reagent, 15.0 mmol), the reaction flask was warmed to −15° C., stirred for 45 minutes, treated with brine (20 mL), and the clear homogeneous mixture was extracted with ethyl acetate (2×40 mL). The organic portions were combined, washed with aqueous KHSO4 solution (15 mL), aqueous NaHCO3 solution (15 mL), and brine (15 mL), and dried (MgSO4). Filtration and removal of solvent provided 1.68 g of the desired product as a white solid.

1. extractionthe clear homogeneous mixture was extracted with ethyl acetate (2×40 mL)
2. washwashed with aqueous KHSO4 solution (15 mL), aqueous NaHCO3 solution (15 mL), and brine (15 mL)
3. dry with materialdried (MgSO4)
4. filtrationFiltration and removal of solvent

ORD record

ord-300960435c954b259cd8839d27437a5a

Source dataset

uspto-grants-2003_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06645968B2