4-Methylmorpholine → (S)-methyl 4-(tert-butoxycarbonylamino)-5-hydroxypentanoate

HRID 421590Notes

Reaction equation

HRID 421590 reaction equation
[C:1]([O:5][C:6]([NH:8][C@@H:9]([CH2:13][CH2:14][C:15]([O:17][CH3:18])=[O:16])[C:10](O)=[O:11])=[O:7])([CH3:4])([CH3:3])[CH3:2].CN1CCOCC1.ClC(OCC)=O.[BH4-].[Na+]>C1COCC1>[C:1]([O:5][C:6]([NH:8][C@H:9]([CH2:10][OH:11])[CH2:13][CH2:14][C:15]([O:17][CH3:18])=[O:16])=[O:7])([CH3:3])([CH3:2])[CH3:4]

Participants

6

Conditions

Temperature
-10 °C

Procedure

In a round-bottom flask, (2S)-2-[(tert-butoxy)carbonylamino]-4-(methoxycarbonyl)butanoic acid (78 mmol, 20.36 g) was dissolved in THF (300 mL). The solution was cooled to −10° C. and N-methylmorpholine (78 mmol, 8.58 mL) and ethyl chloroformate (78 mmol, 7.48 mL) were added, followed by sodium borohydride (234 mmol, 8.85 g). The reaction was stirred for 30 min at this temperature and then quenched by slow addition of saturated solution of ammonium chloride until no further evolution of hydrogen was observed. The reaction mixture was then extracted with ethyl acetate and dried over magnesium sulfate. After filtration, solvent was evaporated and the crude material was purified by column chromatography (SiO2, 1:1 n-hexanes/ethyl acetate) to yield the title compound (11.68 g, 61% yield). ES-MS: 248 (M+1).

Workup

  1. customquenched by slow addition of saturated solution of ammonium chloride until no further evolution of hydrogen
  2. extractionThe reaction mixture was then extracted with ethyl acetate
  3. dry with materialdried over magnesium sulfate
  4. filtrationAfter filtration, solvent
  5. customwas evaporated
  6. customthe crude material was purified by column chromatography (SiO2, 1:1 n-hexanes/ethyl acetate)

Sources & evidence

ORD record
ord-8333a9c7b08a4f16886717228d2c2c8d
Source dataset
uspto-grants-2012_01
Patent number
US08101588B2

Reaction notes

Loading…