Some Analogs of Chlordiazepoxide 63 mixture was then heated under reflux for 2.5 hr., kept 16 hr.; the solid filtered, the filtrate cooled, and extracted with 750 ml. of cold 20% hydrochloric acid. With continued ice-cooling, the acid extract was made alkaline with solid potassium carbonate and the base extracted with ether. Concentration of the dried ether extract and distillation of the residue gave 142.3 g. (81% yield) of the base, b.p. 57-60°( 1 mm.), h«d 1.4773.