Potassium Carbonate → HCID 53959266, compound

Participants

Reaction Steps

A mixture of 5.0 g (21.8 mmol) of ethyl 2-methoxyimino-4-oxooctanoate (from Example 1, Step A), 3.6 g (26 mmol) of anhydrous potassium carbonate, and 70 mL of dry DMF was stirred under N2 at room temperature for 1 hour. The mixture was then cooled to 0° C. and treated dropwise with a solution of 5.9 g (21.8 mmol) of 4-bromo-2-fluorobenzyl bromide in 20 mL of dry DMF. The mixture was allowed to warm slowly to room temperature and was stirred under N2 for 48 hours. The mixture was partitioned between 400 mL of ethyl acetate and 400 mL of 0.2N HCl. The organic layer was washed twice with H2O and then dried over Na2SO4. The filtered solution was concentrated, and the residual oil was flash chromatographed on silica gel. Gradient elution with 5-20% ethyl acetate in hexane afforded 3.51 g (39%) of the title compound as an oil; homogeneous by TLC in 3:1 hexane-EtOAc; mass spectrum (FAB) m/e 416, 418 (M+1)+. 200 MHz 1H NMR (CDCl3) δ0.87 (t, J=7.1 Hz, 3H), 1.2-1.4 (m, 5H) including 1.25 (t, J=7.1 Hz, 3H), 1.55 (m, 2H), 2.31 (t, J=7.1 Hz, 2H), 2.97 (dd, J=14, 10 Hz, 1H), 3.36 (dd, J=14, 5 Hz, 1H), 3.95 (s, 3H), 4.15-4.35 (m, 3H), 6.98 (dd, J≈8, 8 Hz, 1H), 7.15 (apparent d, J=8.2 Hz, 2H).

Provenance & Evidence