1-Azaphenothiazine carboxylic acid chloride

Azaphenothiazine carboxylic acid chloride Piperidinoethoxy ethanol... 

B.5 parts of 1 -azaphenothiazine carboxylic acid chloride and 14 parts of piperidino-ethoxy-ethanol were introduced into 100 parts of chlorobenzene and the mixture boiled under reflux for 5 minutes. After cooling off the precipitated hydrochloride salt of piperidino-ethoxy-ethanol was filtered off on a suction filter. Water was added to the filtrate and the pH thereof adjusted to 5 to 6 with dilute HCI. The aqueous phase was then removed, a caustic soda solution added thereto and then extracted with ether. The ethyl extract waswashed with water, then dried with potash and the ether distilled off. 9.4 parts of the piperidino-ethoxy-ethyi ester of 1 -azaphenothiazine carboxylic acid were obtained. This product was dissolved in 20 parts of isopropanol and the solution neutralized with isopropanolic HCI. The monohydrochloride which precipitated out after recrystallization from isopropanol had a melting point of 160°Cto 161°C. 

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