Sodium borohydride → HCID 13727777, compound

HRID 652355Notes

Reaction equation

HRID 652355 reaction equation
[C:1]([O:5][C:6]([NH:8][C@@H:9]([CH2:28][CH:29]([CH3:31])[CH3:30])[C:10](=[O:27])[CH2:11][NH:12][C@H:13]([C:18]([O:20][CH2:21][CH2:22][Si:23]([CH3:26])([CH3:25])[CH3:24])=[O:19])[CH2:14][CH:15]([CH3:17])[CH3:16])=[O:7])([CH3:4])([CH3:3])[CH3:2].[BH4-].[Na+]>O1CCCC1.O>[C:1]([O:5][C:6]([NH:8][C@@H:9]([CH2:28][CH:29]([CH3:31])[CH3:30])[CH:10]([OH:27])[CH2:11][NH:12][C@H:13]([C:18]([O:20][CH2:21][CH2:22][Si:23]([CH3:24])([CH3:25])[CH3:26])=[O:19])[CH2:14][CH:15]([CH3:16])[CH3:17])=[O:7])([CH3:2])([CH3:3])[CH3:4]

Participants

5

Reactant 2

HCID 4311764Sodium borohydrideHCID 13727775HCID 13727775, compound

Product 1

HCID 13727777HCID 13727777, compoundYield 69.7%

Reagents, catalysts & solvents 2

HCID 962WaterSolvent2×HCID 8028TetrahydrofuranSolvent

Procedure

To a solution of 5.0 g (10.9 mmol) of N-[(3S)-3-[[(t-butyloxy)carbonyl]amino]-2-oxo-5-methylhexyl]-L-leucine, 2-(trimethylsilyl)ethyl ester in a mixture of 150 ml of tetrahydrofuran and 50 ml of water cooled in an ice-water bath was added 2.1 g (54.5 mmol) of sodium borohydride. After 5 minutes, the reaction was poured into 300 ml of water and extracted with 600 ml of ethyl acetate. The organic extract was rinsed further with water and brine, dried (magnesium sulfate) and concentrated in vacuo to yield 4.7 g of crude product. Flash chromatography on 140 g of LPS-1 silica gel eluted with 10:1, petroleum ether:acetone yielded 3.5 g of the title compound as an oil. By 13C-NMR analysis, material prepared in this manner is essentially a 1:1 mixture of diastereomers.

Workup

  1. temperaturecooled in an ice-water bath
  2. extractionextracted with 600 ml of ethyl acetate
  3. extractionThe organic extract
  4. washwas rinsed further with water and brine
  5. dry with materialdried (magnesium sulfate)
  6. concentrationconcentrated in vacuo
  7. customto yield 4.7 g of crude product
  8. washFlash chromatography on 140 g of LPS-1 silica gel eluted with 10:1, petroleum ether

Sources & evidence

ORD record
ord-53afd7c53c0d4211b2baf5e65a8f6487
Source dataset
uspto-grants-1987_06
Patent number
US04670541

Reaction notes

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