Dimethyl malonate → Dimethyl2-[2-(4-fluorophenyl)-2-oxoethyl]-2-[2-[4-(methylsulfonyl)phenyl]-2-oxoethyl]propanedioate

Beteiligte Stoffe

Reaktionsschritte

To a solution of 7.18 mL (63 mmol) of dimethyl malonate in 160 mL of DMF at 0° C. under an atmosphere of nitrogen was added 3.0 g (75 mmol) of sodium hydride (60% suspension in oil). The reaction was stirred at ambient temperature for 15 minutes (or until the gas evolution has ceased), cooled to -20° C., and treated with 15 g (69 mmol) of 2-bromo-4'-fluoroacetophenone (Aldrich) in one portion. The mixture was stirred at ambient temperature for 1 hour and then cooled to 0° C.; another 75 mmol of sodium hydride was added and the resulting mixture stirred at ambient temperature for 15 minutes (or until the gas evolution has ceased). The reaction was recooled to -20° C. and treated with 19.1 g (69 mmol) of 2-bromo-4'-(methylsulfonyl)acetophenone (prepared in Step 3). The reaction was stirred at room temperature for 2 hours and concentrated in vacuo. The residue was partitioned between water and ethyl acetate; the ethyl acetate phase was dried (MgSO4) and reconcentrated in vacuo. The residue was chromatographed on silica gel to give 13.8 g (51%) of dimethyl2-[2-(4-fluorophenyl)-2-oxoethyl]-2-[2-[4-(methylsulfonyl)phenyl]-2-oxoethyl]propanedioate as an oil: NMR (CDCl3) δ 3.06 (s, 3H), 3.76 (s, 6H), 4.03 (s, 2H), 4.08 (s, 2H), 7.13 (t, J=8.6 Hz, 2H), 7.97-8.05[m with d at 8.03 (J=8.7 Hz), 4H], 8.14 (d, J=8.5 Hz, 2H).

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