active principles of the pituitary gland 573 arranged through a mercury seal, and a thermometer the bulb of which was immersed in the liquid when the material melted. The mixture was heated with stirring; carbon dioxide evolution was appreciable at 200°, and it was allowed to escape through the side tube of the flask and to bubble through water, which gave an indication of the progress of the reaction. The temperature was allowed to rise and was maintained at 260°until carbon dioxide evolution ceased (about four hours). It is necessary to continue until the carbon dioxide evolution has completely stopped. If a distillation is attempted before this point, a considerable quantity of anthraquinone is formed, which contaminates the product.The stirrer was taken from the flask, a short air condenser attached to the side tube and the thermometer raised out of the liquid as for distillation.The crude benzophenone was distilled over until the drops of distillate became dark in color; the weight of this crude product was 209 g., 86.6% of the theoretical. One crystallization from 95% alcohol gave pure benzophenone, m. p. 47^8°, in an amount corresponding to 82-84% of the theoretical based on the o-benzoylbenzoic acid. The crystallization may be replaced by distillation in a vacuum.

No abstract

No abstract

No abstract

No abstract