Hydrochloric Acid → HCID 23005244, compound

Participants

Reaction Steps

A mixture of 4-(4′-methylsulfanyl-biphenyl-4-yl)-4oxo-butyric acid, methyl ester (0.3742 g, 0.001190 mol) and 1.0 M aqueous sodium hydroxide (1.3 mL, 0.0013 mol) in tetrahydrofuran-methanol (5 mL/5 mL) was stirred at room temperature for 3 days. The volatiles were rotary evaporated, and the residue was suspended in water. The suspension was acidified with 1.0 M aqueous hydrochloric acid (1.4 mL, 0.0014 mol), and the mixture was extracted with tetrahydrofuran-dichloromethane (50/50 v/v). The organics were washed with brine, dried (Na2SO4) and rotary evaporated to give 0.34 g of crude 4-(4′-methylsulfanyl-biphenyl-4-yl)-4-oxo-butyric acid as an off-white solid. A portion of this material (0.3383 g, 0.001 1 mol) was stirred with hydroxylamine hydrochloride (0.0931 g, 0.00134 mol) in the presence of sodium carbonate (0.1438 g, 0.001357 mol) in absolute ethanol (7 mL) at reflux for 20 hours and allowed to cool. The volatiles were rotary evaporated, and the residue was partitioned between dichloromethane-tetrahydrofuran (50/50, v/v) and 0.10 M aqueous hydrochloric acid (25 mL). The organics were washed with brine, dried (Na2SO4) and rotary evaporated. The residue was dissolved in tetrahydrofuran, silica gel (4.0 g) was added, and the mixture was rotary evaporated to dryness. The resulting powder was chromatographed on silica gel (48 g, 230-400 mesh), eluting with dichloromethane-diethyl ether (24:1, 13×50 mL); dichloromethanemethanol (24:1, 13×50 mL; 20:1, 10×50 mL) to give 0.0525 g of 4-hydroxyimino-4-(4′-methylsulfanyl-biphenyl-4-yl)-butyric acid as a white solid; mp 162-164° C.

Provenance & Evidence