Glyoxylic Acid → HCID 18786409, compound

Participants

Reaction Steps

To 10 mL of concentrated sulfuric acid was added 2.31 g of [(2,6-difluorobenzoyl)amino]hydroxyacetic acid (prepared as for the known α-hydroxyhippuric acid from glyoxylic acid and 2,6-difluorobenzamide) and 2.50 g of S-([1,1'-biphenyl]4-yl) dimethylcarbamothioate, and this mixture was stirred for 2 h and poured over ice. The yellow precipitate was collected and washed with water, dissolved in ethyl acetate, and dried over magnesium sulfate. This solution was concentrated until a white precipitate formed, which was collected and washed with 50% ethyl acetate/hexane and dried to afford 2.07 of solid. To a solution of this solid in 15 mL of methanol was added 0.56 mL of thionyl chloride, and this mixture was stirred and heated at reflux for 3.5 h. After the addition of 16 mL of 1N NaOH to the reaction mixture, volatiles were removed on a rotary evaporator, and the residual mixture was extracted with ethyl acetate, and the extract was dried over magnesium sulfate. Concentration of the solution and addition of hexane produced a white solid, which was collected and dried to afford the named compound, 0.27 g. The remaining material was adsorbed onto silica gel, applied to a column of silica gel, and eluted with 60% ethyl acetate/hexane to afford an additional 1.04 g of the named compound. 1H-NMR(CDCl3, 300 MHz): δ3.0-3.2 (br d, 6H), 3.8 (s, 3H), 5.8 (d, 1H), 6.9-7.0 (m, 2H), 7.2 (br d, 1H), 7.4 (m, 1H), 7.5-7.6 (m, 8H).

Provenance & Evidence