Potassium Permanganate → methyl 2-[2-[(E)-N-methoxy-C-[3-(trifluoromethyl)phenyl]carbonimidoyl]phenyl]-2-oxoacetate

Participants

Reaction Steps

A solution of (E,E)-methyl 3-methoxy-2-[2-(methyl(3-trifluoromethyl-phenyl)oximinomethyl)phenyl]propenoate (2.0 g as prepared in EP-A-0370629) in dichloromethane (20 ml) was added to potassium permanganate (0.93g) in water (20 ml) containing tetra-n-hexyl-ammonium hydrogensulphate (0.1 g). After stirring for 2 hours, the reaction mixture was poured into sodium metabisulphite solution (40 mls of a 10% aqueous solution) and extracted with dichloromethane. The combined organic extracts were dried, concentrated and chromatographed using a mixture of ether and hexane (1:1) as the eluant to give (E)-methyl 2-[methyl(3-trifluoromethylphenyl)oximinomethyl]phenylglyoxalate (1.01 g, 54% yield) as a clear oil; 1H NMR : δ2.31(3H,s), 3.92(3H,s), 5.60(2H,s), 7.4-7.9(8H,m) ppm; IR maxima (film): 1740, 1686 cm-1.

Provenance & Evidence