1,8-Diazabicyclo(5.4.0)undec-7-ene → diethyl (2S,3S)-oxirane-2,3-dicarboxylate

HRID 1478619Notes

Reaction equation

HRID 1478619 reaction equation
Br[C@H:2]([C@H:8]([OH:14])[C:9]([O:11][CH2:12][CH3:13])=[O:10])[C:3]([O:5][CH2:6][CH3:7])=[O:4].C1CCN2C(=NCCC2)CC1>CCOCC>[O:14]1[C@H:2]([C:3]([O:5][CH2:6][CH3:7])=[O:4])[C@H:8]1[C:9]([O:11][CH2:12][CH3:13])=[O:10]

Participants

4

Reactant 2

HCID 811841,8-Diazabicyclo(5.4.0)undec-7-eneHCID 13002922Diethyl (2R,3R)-2-bromo-3-hydroxybutanedioate

Product 1

HCID 7021072diethyl (2S,3S)-oxirane-2,3-dicarboxylateYield 80.7%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

2a (38.1 g, 142 mmol) was dissolved in anhydrous Et2O (100 ml) and DBU (32.3 g, 212.4 mmol, in Et2O [50 ml]) was added dropwise at 0° C. for 1 h. The reaction was allowed to warm to r.t. and stirred for an additional 4 h. Reaction was quenched with cold 1N HCl to pH˜5. The resulting aqueous layer was extracted with Et2O (3×150 ml). The combined organic extracts were washed with brine (2×100 ml), dried over Na2SO4, and concentrated to give the pure product as faintly yellow oil (21.5 g, 80.7% yield). Product purity typically reflects that of the bromohydrin starting material. If necessary, fractional vacuum distillation can be used for purification. 1H NMR (CDCl3, 400 MHz): δ 4.36-4.22 (m, 4H); 3.67 (s, 2H); 1.35-1.31 (t, 6H). 13C NMR (CDCl3, 100 MHz): 166.75, 62.21, 52.01, 14.01.

Workup

  1. customReaction
  2. customwas quenched with cold 1N HCl to pH˜5
  3. extractionThe resulting aqueous layer was extracted with Et2O (3×150 ml)
  4. washThe combined organic extracts were washed with brine (2×100 ml)
  5. dry with materialdried over Na2SO4
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-2a19a70045d1453dadfaf8ba197616d7
Source dataset
uspto-grants-2016_08
Patent number
US09403843B2

Reaction notes

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