Niacin chloride hydrochloride

To a solution of 142 g (1 mol) of trans-3,3 -trimethylcyclohexenol 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. 

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