Pyridine → N-(4-Chloro-phenyl)-2-(2,2-dimethyl-5-oxo-[1,3]dioxolan-4-ylidene)-N-(4-methyl-benzyl)-acetamide

Participants

Reaction Conditions

Reaction Steps

A solution of (Z)-2,2-dimethyl-5-(chlorocarbonylmethylene)-1,3-dioxolan-4-one (0.553 g, 2.90 mmol) in dry dichloromethane (5 ml) was added dropwise to a cold (0-5° C.) solution of (4-chlorophenyl)-(4-methylbenzyl)-amine (0.545 g, 2.35 mmol) (Ballistreri et al., J. Org. Chem., 41, 1976, 3364), pyridine (0.35 ml) and a small crystal of 4-N,N-dimethylaminopyridine in dry dichloromethane (10 ml). After 30 min, the cooling bath was removed and the resulting clear solution was stirred at 22° C. for another 30 min. The reaction mixture was then diluted wih ethyl acetate, washed with saturated sodium bicarbonate, brine and dried (magnesium sulfate). Evaporation of the solvent in vacuo, filtration of the residue on a short silica gel pad (elution-toluene ethyl acetate; 85:15) followed by crystallization from ethyl acetate-hexane gave 0.794 g (87%) of the title amide as white needles: mp 149° C. 1HNMR 400 MHz (CDCl3) δ (ppm): 1.72 (6H, s, CH3), 2.31 (3H, s, CH3), 4.88 (2H, s, NCH2), 5.64 (1H, s, CH), 6.93 (2H, d, J=8.5 Hz, aromatics), 7.08 (4H, m, aromatics), 7.3 (2H, d, J=8.5 Hz, aromatics). Anal. Calcd for C21H20ClNO4: C, 65.37; H, 5.22; N, 3.63. Found: C, 65.22; H, 5.25; N, 3.52.

Provenance & Evidence