Reaction #640597

Reaction equation

MeI

solution

Methyl (4(S)-phenyloxazolidin-2-on-3-yl)acetate

lithium bis(trimethylsilyl)amide

→

title compound

Methyl 2-(4(S)-phenyloxazolidin-2-on-3-yl)propanoate

Solvents

THF

THF

Conditions

Workup

1. 1
   OtherUpon complete conversion of the azetidinone, the reaction was quenched with saturated aqueous NH4Cl
2. 2
   Otherpartitioned between EtOAc and water
3. 3
   WashThe organic layer was washed sequentially with saturated aqueous sodium bisulfite, and saturated aqueous NaCl
4. 4
   DryingThe resulting organic layer was dried (MgSO4)
5. 5
   Otherevaporated

Procedure

A solution of Example 2A (1 g, 4.25 mmol) in 10 mL of anhydrous THF at −78° C. was treated with 4.68 mL (4.68 mmol) of a 1 M solution of lithium bis(trimethylsilyl)amide in THF. The reaction mixture was stirred for 1 h. at about −70° C. before adding MeI (1.59 mL, 25.51 mmol). Upon complete conversion of the azetidinone, the reaction was quenched with saturated aqueous NH4Cl and partitioned between EtOAc and water. The organic layer was washed sequentially with saturated aqueous sodium bisulfite, and saturated aqueous NaCl. The resulting organic layer was dried (MgSO4) and evaporated to afford the title compound (a mixture of diasteromers) as a white solid (1.06 g, 93%); 1H NMR (CDCl3) δ 1.07/1.53 (d/d, J=7.5 Hz, 3H), 3.59/3.74 (s/s, 3H), 3.85/4.48 (q/q, J=7.5 Hz, 1H), 4.10-4.14 (m, 1H), 4.60-4.64/4.65-4.69 (m/m, 1H), 4.88-4.92/4.98-5.02 (m/m, 1H), 7.24-7.40 (m, 5H).

Source