4-Methylmorpholine → HCID 86745452, compound

Temperature

-25 °C

A solution of Boc-Norleucine (6.9 g, 30 mmol) in ethyl acetate (EtOAc) (80 mL) was cooled to -25° C. and N-methylmorpholine (3.3 mL, 30 mmol) was added followed by isobutyl chloroformate (4.2 mL, 32 mmol). The mixture was stirred for 15 minutes at -25° C. and diethylether (Et2O) (50 mL) was then added. After cooling the mixture to -50° C., the white precipitate was filtered under N2 and the cold filtrate was treated with a solution of diazomethane in Et2O (130 mL, 0.4 M, 52 mmol). The mixture was allowed to proceed overnight, gradually warming up to room temperature. Excess of diazomethane was removed by bubbling a N2 stream through the solution and the solvent was then evaporated. The residual oil was dissolved in EtOAc (100 mL) and was washed with saturated NaHCO3 (1×100 mL) and brine (1×100 mL). The organic layer was dried over Na2SO4, filtered and concentrated to yield 7.5 g (98)% of crude product.

1. temperatureAfter cooling the mixture to -50° C.
2. filtrationthe white precipitate was filtered under N2
3. waitto proceed overnight
4. temperaturegradually warming up to room temperature
5. customExcess of diazomethane was removed
6. customby bubbling a N2 stream through the solution
7. customthe solvent was then evaporated
8. dissolutionThe residual oil was dissolved in EtOAc (100 mL)
9. washwas washed with saturated NaHCO3 (1×100 mL) and brine (1×100 mL)
10. dry with materialThe organic layer was dried over Na2SO4
11. filtrationfiltered
12. concentrationconcentrated
13. customto yield 7.5 g (98)% of crude product

ORD record

ord-98541680699745a682af9dc37eed6e69

Source dataset

uspto-grants-1992_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05086165