Pyridine → 2-(2,2-Dimethyl-5-oxo-[1,3]dioxolan-4-ylidene)-N-(4-fluoro-benzyl)-N-methoxy-acetamide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of (2,2-dimethyl-5-oxo-[1,3]dioxolan-4-ylidene)-acetyl chloride, Compound 1-B, (2.45 g, 12.9 mmol) in dichloromethane (15 ml) was added dropwise over 10 minutes to a cold (0-5° C.) mixture of N-4-fluorobenzyl-O-methyl-hydroxylamine (2.0 g, 12.9 mmol) and pyridine (2.1 ml, 25.7 mmol) in dichloromethane (50 ml). The cooling bath was then removed and the solution was stirred at 22° C. for 30 minutes. The reaction mixture was then quenched by the addition of water and ethyl acetate. The organic phase was washed successively with 0.1 N hydrochloric acid, saturated sodium bicarbonate, brine and dried (magnesium sulfate). Evaporation of the solvent and chromatography of the residue on silica gel (toluene-ethyl acetate, 8:2) gave 3.72 g (93% yield) of the title amide as white crystals: mp 111° C. (ethyl acetate-hexane). 1H NMR 400 MHz (CDCl3) δ (ppm): 1.75 (6H, s), 3.68 (3H, s), 4.79 (2H, s), 6.38 (1H, s), 7.0 (2H, m), 7.34 (2H, m). Anal. calcd for C15H16FNO5: C, 58.25; H, 5.21; N, 4.52. Found: C, 58.33; H, 5.38; N, 4.51.

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