Bucetin may be prepared from acetoacetic acid p-phenetidide as follows:
5.5 parts of acetoacetic acid p-phenetidide, suspended in 600 parts by volume
of methanol, are hydrogenated at 80°-85°C with a nickel catalyst supported
on kiesel-guhr. When the theoretical quantity of hydrogen has been absorbed,
the solution is cooled, then filtered, and the filtrate is concentrated. The solid
residue is recrystallized from six times its weight of isopropanol. β-
Hydroxybutyric acid p-phenetidide is obtained in an almost quantitative yield
in the form of white crystals which melt at 160°C.
55 parts of acetoacetic acid p-phenetidide, suspended in 500 parts by volume
of methanol, are hydrogenated with Raney nickel at 70°C. When the
theoretical quantity of hydrogen has been absorbed, the solution is cooled,
then filtered, and the filtrate is concentrated. The solid residue is recrystallized
from six times its weight of isopropanol. 51 parts (93 % of the theoretical
yield) of β-hydroxybutyric acid p-phenetidide are obtained in the form of white
crystals, which are sparingly soluble in water and melt at 160°C.
A mixture of 5 g of aluminum amalgam, 5 g of acetoacetic acid p-phenetidide
and 50 ml of ethanol are gently heated for 30 minutes. After filtering off the
reducing agent with suction, water is added to the filtrate, and the latter is
then acidified with 2 N hydrochloric acid. β-Hydroxybutyric acid p-phenetidide
melting at 160°C crystallizes in almost quantitative yield in the form of white
crystals.
