(2R,3S)-N-(tert-Butyloxy)carbonyl-3-amino-2-acetoxy-4-phenylbutanal → (2S,3R,4S)-N-[(tert-Butyloxy)carbonyl]-2-amino-1-phenyl-3,4-dihydroxy-6-methylheptane

HRID 484161Notes

Reaction equation

HRID 484161 reaction equation
[C:1]([O:5][C:6]([NH:8][C@@H:9]([CH2:17][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)[C@@H:10]([O:13]C(=O)C)[CH:11]=[O:12])=[O:7])([CH3:4])([CH3:3])[CH3:2].[CH2:24]([Mg]Cl)[CH:25]([CH3:27])[CH3:26]>C1COCC1.CCOCC.CO.O>[C:1]([O:5][C:6]([NH:8][C@H:9]([C@@H:10]([OH:13])[C@@H:11]([OH:12])[CH2:24][CH:25]([CH3:27])[CH3:26])[CH2:17][C:18]1[CH:19]=[CH:20][CH:21]=[CH:22][CH:23]=1)=[O:7])([CH3:2])([CH3:3])[CH3:4]

Participants

6

Procedure

The oil prepared in Example 2 was dissolved under nitrogen in 100 mL of dry THF and cooled to -70° . To this solution was added 13 mL (26mmol) of a 2.0M solution of isobutylmagnesium chloride in ether and the stirred mixture was allowed to warm to room temperature and stir for 2 hrs. After decomposition with MeOH/H2O the mixture was diluted with ether, washed with saturated NH4Cl solution twice, then dried and the solvents stripped off under vacuum. The residue was allowed to stand overnight in 80% MeOH-H2O containing excess ammonium hydroxide. The MeOH was stripped off and the mixture was extracted with ether. These extracts were combined, washed with water, dilute KHSO4, then dried and evaporated to give 2.36 g of a yellow glass which crystallized from 50 mL of pentane on standing overnight. The yellow-white powder obtained was recrystallized from ether-hexane and furnished the title compound (0.41 g) as white, hairy needles, mp 134-136°, Rf (ether): single spot, 0.6. By chromatography of the mother liquors and crystallization of the appropriate fractions, an additional 0.22 g of product, mp 138-139°, was obtained. Anal: Calc'd. for C19H31NO4 (337.45): C, 67.62; H, 9.26; N, 4.15. Found: C, 67.51; H, 9.43; N, 4.24.

Workup

  1. temperaturecooled to -70°
  2. washwashed with saturated NH4Cl solution twice
  3. customdried
  4. waitto stand overnight in 80% MeOH-H2O containing excess ammonium hydroxide
  5. extractionthe mixture was extracted with ether
  6. washwashed with water, dilute KHSO4
  7. customdried
  8. customevaporated

Sources & evidence

ORD record
ord-c206a3b1b43e4a46810cd0d692624b60
Source dataset
uspto-grants-1993_07
Patent number
US05229420

Reaction notes

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