Dimethylformamide → 4-({[2-(2,2-Dimethyl-5-oxo-[1,3]dioxolan-4-ylidene)-acetyl]-methoxy-amino}-methyl)-n-methyl-benzamide

Participants

Reaction Steps

A solution of 4-({[2-(2,2-dimethyl-5-oxo-[1,3]dioxolan-4-ylidene)-acetyl]-methoxy-amino}-methyl)-benzoic acid (0.150 g, 0.45 mmol) in dichloromethane (2 ml) was treated at 22° C. with oxalyl chloride (0.08 ml) and a trace (capillary) of N,N-dimethylformamide and the resulting mixture was stirred for 2 h. The solvent and excess reagent were evaporated in vacuo and the residue was dissolved in dichloromethane (2 ml). This solution was added dropwise to a cold (5° C.) solution of methylamine (0.5 mmol, 0.25 ml of a 2M solution in tetrahydrofuran) and pyridine (0.01 ml) in dichloromethane (2 ml). After 1 h at 22° C., the reaction mixture was diluted with ethyl acetate, washed successively with 0.1 N hydrochloric acid, saturated sodium bicarbonate, brine and dried over anhydrous magnesium sulphate. Evaporation of the solvent under reduced pressure and chromatography of the residue on silica gel (elution ethyl acetate and acetonitrile, 0 to 5%) yielded 0.060 g (38% yield) of the title amide as a white solid. 1HNMR 400 MHz (DMSO-d6) δ (ppm): 1.69 (6H, s, CH3), 2.77 (3H, d, J=4.5 Hz, NCH3), 3.72 (2H, s, OCH3), 4.85 (2H, s, NCH2), 6.18 (1H, s, CH), 7.35 (2H, d, J=8.2 Hz, aromatics), 7.79 (2H, d, J=8.2 Hz, aromatics), 8.41 (1H, broad q, NH).

Provenance & Evidence