Manufacturing Process
It was mixed 120 parts of urea and 258 parts of bromodiethylacetylbromide
(prepared from diethylacetic acid anhydride and bromine). After 12 hours the
mixture was heated for 3 hours at 100°C. The product was mixed with an
aqueous solution of sodium bicarbonate and then was filtered. The obtained
bromodiethylacetylurea was crystallized from diluted ethanol; melting point
114-118°C. The mixture of 474 parts of bromodiethylacetylurea, 1000 parts of
acetic anhydride and 75 parts ZnCl2 was heated at 60°C for 1 hour. The
product was stirred with 3000 parts of ice-water and then 1-acetyl-3-(α-
bromo-α-ethylbutyryl)urea was filtered; melting point 108-109°C.
