Dimethyl methylphosphonate → Dimethyl [3-(3-chlorophenyl)-2-oxopropyl]phosphonate

Participants

Reaction Steps

To a solution of dimethyl methylphosphonate (4.32 mL, 40 mmol) in anhydrous THF (40 mL), cooled at −78° C. was added n-BuLi (1.6 M in hexane, 27.5 mL, 44 mmol). The mixture was stirred for 30 minutes at this temperature under nitrogen. Methyl 3-chlorophenylacetate (3.69 mL, 20 mmol) was added dropwise for 10 minutes. The mixture was stirred for 2 hours at −78° C., gradually was warm to room temperature. The mixture was quenched with addition of 1N HCl to pH 4-5. The organic layer was separated, washed with brine and dried over MgSO4. The residue was purified through flash chromatography on silica gel (MeOH/CH2Cl2 1.5/98.5) to give the product (1.43 g) with colorless oil in 26% yield. 1H-NMR (CDCl3) δ 3.07 (d, J=21 Hz, 2H), 3.750 (s, 3H), 3.775 (s, 3H), 3.873 (s, 2H), 7.01 (t, J=8.0 Hz, 1H), 7.19 (s, 1H), 7.28 (d, J=8.0 Hz, 2H).

Provenance & Evidence