Pacatal,Warner Lambert,US,1957
A 500 cc flask equipped with a mechanical stirrer, reflux condenser and a soda-lime tube was filled with 230 cc of absolute xylene, 27.5 g of 1-methyl3-bromomethylpiperidine, 53.3 g of phenothiazine and 14.2 g of finely powdered sodium amide, and the solution was heated under reflux for 6 hours. After cooling water was added and the batch was extracted with ether. As the hydrochloric acid salt of the obtained phenothiazine derivative is difficultly soluble in water, the further processing was carried out by way of the acetate. The etheric solution was extracted several times in a separating funnel with dilute acetic acid. The combined aqueous extracts were basified, extracted with ether, dried with potassium carbonate and, after removal of the ether, distilled in vacuo.
Yield = 64%; boiling point 230°C to 235°C at 4 mm; melting point of
hydrochloride is 180°C to 181°C.
