Manufacturing Process
To a solution of 142 g (1 mol) of trans-3,3,5-trimethylcyclohexanol in 400 cc
of anhydrous benzene heated to 70 C is added gradually 178 g (1 mol) of
niacin chloride hydrochloride. Heating is carried out under reflux conditions for
3 hours, the solution is cooled, the ester hydrochloride is filtered off and then
recrystallized in an ethanol-ethyl ether mixture to obtain 227 g (80% yield) of
product melting at 155°C to 157°C.
By treating the hydrochloride with an aqueous solution of NaOH at 0°C, the
free base is obtained in the form of a viscous white liquid which boils at 115°C
under 0.05 mm.
