Diisopropylethylamine → (R)-tert-butyl 4-((1R,2R)-3-((R)-4-benzyl-2-oxooxazolidin-3-yl)-1-hydroxy-2-methyl-3-oxopropyl)-2,2-dimethyloxazolidine-3-carboxylate

HRID 2046819Notes

Reaction equation

HRID 2046819 reaction equation
[CH2:1]([C@@H:8]1[CH2:12][O:11][C:10](=[O:13])[N:9]1[C:14](=[O:17])[CH2:15][CH3:16])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.CCN(C(C)C)C(C)C.[CH:27]([C@H:29]1[CH2:33][O:32][C:31]([CH3:35])([CH3:34])[N:30]1[C:36]([O:38][C:39]([CH3:42])([CH3:41])[CH3:40])=[O:37])=[O:28]>C(Cl)Cl.Cl[Ti](Cl)(Cl)Cl>[CH2:1]([C@@H:8]1[CH2:12][O:11][C:10](=[O:13])[N:9]1[C:14](=[O:17])[C@H:15]([CH3:16])[C@H:27]([C@H:29]1[CH2:33][O:32][C:31]([CH3:35])([CH3:34])[N:30]1[C:36]([O:38][C:39]([CH3:42])([CH3:41])[CH3:40])=[O:37])[OH:28])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

6

Conditions

Temperature
-40 °C

Procedure

To a solution of (R)-4-benzyl-3-propionyloxazolidin-2-one (1.0 equiv.) in DCM (0.13 M) was added TiCl4 (1.0 equiv.) at −40° C. The mixture was stirred at −40° C. for 10 min (yellow suspension), then DIPEA (2.5 equiv.) was added (dark red solution) and stirred at 0° C. for 20 min. (R)-tert-butyl 4-formyl-2,2-dimethyloxazolidine-3-carboxylate (1.0 equiv.) in DCM (0.5 M) was then added dropwise and the resulting mixture was stirred for 1.5 hours. The reaction was quenched by the addition of aqueous ammonium chloride and the mixture was extracted with ethyl acetate. The organic phase was separated, washed with brine, dried with magnesium sulfate, filtered, and concentrated. The residue was purified via column chromatography eluting with ethyl acetate and hexanes (1:4) to give (R)-tert-butyl 4-((1R,2R)-3-((R)-4-benzyl-2-oxooxazolidin-3-yl)-1-hydroxy-2-methyl-3-oxopropyl)-2,2-dimethyloxazolidine-3-carboxylate as the major product (5:2) in 58% yield. LC/MS=363.3 (M+H-Boc), Rt=1.09 min.

Workup

  1. additionwas then added dropwise
  2. stirringthe resulting mixture was stirred for 1.5 hours
  3. customThe reaction was quenched by the addition of aqueous ammonium chloride
  4. extractionthe mixture was extracted with ethyl acetate
  5. customThe organic phase was separated
  6. washwashed with brine
  7. dry with materialdried with magnesium sulfate
  8. filtrationfiltered
  9. concentrationconcentrated
  10. customThe residue was purified via column chromatography
  11. washeluting with ethyl acetate and hexanes (1:4)

Sources & evidence

ORD record
ord-d7992c9f3dc64b3d9107eefd620b7f44
Source dataset
uspto-grants-2013_11
Patent number
US08592455B2

Reaction notes

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