Hydrochloric Acid → HCID 14500717, compound

Participants

Reaction Steps

A stirred solution of 5.1 g (0.035 mole) of 4-(2-butyl)-3-thiosemicarbazide in 40 mL of absolute ethanol was treated with 5.7 g (0.035 mole) of ethyl 2-chloroacetoacetate and stirred at ambient temperature for 3 hr. The mixture was treated with 20 mL of 2N ethanolic hydrogen chloride, heated at reflux for 1 hr and stirred for ~16 hr at ambient temperature. The reaction mixture after filtering and concentrating in vacuo gave a crude orange solid. A second reaction mixture was prepared with 8.0 g (0.054 mole) of crude 4-(2-buytl)-3-thiosemicarbazide, 50 mL of absolute ethanol, 8.9 g (0.054 mole) of ethyl 2-chloroacetoacetate, and 25 mL of 2N ethanolic hydrogen chloride as described above and gave a crude orange solid. The TLC of both crude products (10% methanol/benzene; silica gel) were identical. Recrystallization of the first batch from acetone/isopropyl ether gave 4 g of fine white crystals, mp 147°-148.5° C. Recrystallization of the second batch from benzene/ligroin gave 2.5 g of pale yellow crystalline product, mp 146°-148.5° C. The 2 solids were combined (6.5 g) and recrystallized from 200 mL of acetone/isopropyl ester (3:1) to give 3.6 g of white fluffy crystals, mp 147°-149° C.

Provenance & Evidence