1-Butanol → HCID 86745839, compound

Participants

Reaction Steps

A mixture of 10.0 g (0.044 mole) of methyl-3-benzoyl-3-chloropropionate and 4.0 g (0.044 mole) of thiosemicarbazide in 50 ml of 1-butanol was refluxed under a nitrogen atmosphere for 32 hours. After cooling to room temperature, the precipitated sulfur was removed by filtration. The filtrate was evaporated under reduced pressure and the residue partitioned between methylene chloride and aqueous 7% sodium bicarbonate. The layers were separated and the organic layer was extracted with water, dried over magnesium sulfate and evaporated under reduced pressure. The residue was dissolved in toluene and chromatographed on an 85 g column of silica gel (47 mm×20 cm) packed in toluene. The column was washed with toluene, methylene chloride, 10% and 50% ethyl acetate-methylene chloride and ethyl acetate, respectively. The fractions containing relatively pure products were combined and evaporated under reduced pressure. The residual oil (4.7 g) was dissolved in isopropanol and treated with 1.5 g (0.017 mole) of anhydrous oxalic acid. The mixture was refluxed until solution was complete, filtered, and the filtrate was treated with isopropyl ether to the cloud point. The oxalate salt of the butyl ester was collected by filtration: 4.8 g (30%), mp 169°-172° C.

Provenance & Evidence