ethyl (2S*,3R*)-3-(t-butyldimethylsilyloxy)-2-(4-methoxybenzylaminomethyl)butanoate → (3S)-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-1-(4-methoxybenzyl)azetidin-2-one

HRID 2255666Notes

Reaction equation

HRID 2255666 reaction equation
[Si:1]([O:8][C@H:9]([CH3:27])[C@H:10]([CH2:16][NH:17][CH2:18][C:19]1[CH:24]=[CH:23][C:22]([O:25][CH3:26])=[CH:21][CH:20]=1)[C:11](OCC)=[O:12])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].C1(C)C=C(C)C=C(C)C=1[Mg]Br>O1CCCC1>[Si:1]([O:8][C@@H:9]([C@@H:10]1[CH2:16][N:17]([CH2:18][C:19]2[CH:24]=[CH:23][C:22]([O:25][CH3:26])=[CH:21][CH:20]=2)[C:11]1=[O:12])[CH3:27])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]

Participants

4

Reactant 2

HCID 57031907ethyl (2S*,3R*)-3-(t-butyldimethylsilyloxy)-2-(4-methoxybenzylaminomethyl)butanoateHCID 178425415HCID 178425415, compound

Product 1

HCID 54758409(3S)-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-1-(4-methoxybenzyl)azetidin-2-oneYield 50.8%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a solution of ethyl (2S,3R)-3-(t-butyldimethylsilyloxy)-2-(4-methoxybenzylaminomethyl)butanoate (7.91 g, crude) in tetrahydrofuran (200 ml) was added dropwise mesitylmagnesium bromide (29 ml) at room temperature. After stirring for 30 minutes, the mixture was quenched with 0.2N hydrochloric acid (250 ml) ethyl acetate (200 ml). The aqueous layer was separated and extracted twice with ethyl acetate. The combined organic layers were washed with 1N hydrochloric acid, saturated aqueous sodium hydrogencarbonate, water and an aqueous sodium chloride in turn, and then dried over magnesium sulfate. The resultant solution was evaporated, and the residue was purified by column-chromatography to give (3S)-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-1-(4-methoxybenzyl)azetidin-2-one (3.55 g).

Workup

  1. customthe mixture was quenched with 0.2N hydrochloric acid (250 ml) ethyl acetate (200 ml)
  2. customThe aqueous layer was separated
  3. extractionextracted twice with ethyl acetate
  4. washThe combined organic layers were washed with 1N hydrochloric acid, saturated aqueous sodium hydrogencarbonate, water
  5. dry with materialan aqueous sodium chloride in turn, and then dried over magnesium sulfate
  6. customThe resultant solution was evaporated
  7. customthe residue was purified by column-chromatography

Sources & evidence

ORD record
ord-a5a62cf226ea488290e804353440a542
Source dataset
uspto-grants-1993_08
Patent number
US05241064

Reaction notes

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