Hydrochloric Acid → HCID 14500687, compound

Participants

Reaction Steps

A stirred slurry of 8 g (0.04 mole) of 4-(3-chlorophenyl)-3-thiosemicarbazide in 75 mL of absolute ethanol was treated with 6.8 g (0.04 mole) of ethyl 2-chloroacetoacetate. The reactants quickly dissolved but a precipitate soon formed. After stirring at room temperature for 2 hr the reaction mixture was treated with 40 mL of 2N ethanolic hydrogen chloride and heated at reflux for 1 hr, then filtered while hot to remove the insoluble sulfur. The filtrate on cooling yielded 3.5 g of yellow solid and an additional 4.7 g was obtained when the filtrate was concentrated in vacuo. Recrystallization from benzene/ligroin gave 4.2 g of pale yellow brown product. Additional ligroin added to the filtrate gave, upon cooling at ~7°-10° C. for ~16 hr, additional crystals but also some oil; this tri-phase mixture was filtered to yield 1.5 g of additional product. Both solids had identical spectra. They were combined and recrystallized twice from benzene/ligroin and finally from benzene by dissolving the solids and reducing the volume until crystallization began. Upon cooling, 3.93 g of beige plate-like crystals were collected, mp 159.5°-160° C.

Provenance & Evidence