Part a: prepare an ice_ cold water bath at the beginning of the experiment tocool the reaction when it becomes vigorously exothermic.
In a 250 ml Erlenmeyer flask, and 6 gm of acetophenone, 6 ml of phenylhygrazine, and 20 gm of polyphosphoric acid. Stir the mixturethoroughly until the temperature rises suddenly_ which indicates the beginning of the reaction. When the temperature starts to rise, cool the mixture immediately with a cold water bath. Maintain thetemperature of the mixture at about 180 °. When the temperature of the reaction mixture no longer rises upon removal of the cold water bath ( which indicates the end of the reaction), add 120 ml of coldwater to the mixture.
Part b: Extract the mixture three times with fresh 30 ml portions of ether.( save all layers until the product is collected). Dry the combined ether extracts over 6 gm of anhydrouspotassium carbonate for about 15 minutes.
Filter and remove the ether by simple distillation using a steam bath as the heat source and a ground-glass flask cooled in an ice-water bath as thereceiver.
Dispose of the recovered diethyl ether in a bottle labeled 2 recovered diethyl ether only”.
The product, 2-phenylindole, can be purified by either recrystallization from methanol or vacuumsublimation. Determine its melting point and submit the product to your instructor.
1 polyphosphoric acid is a glassy viscous liquid. It should be warmed on a steam bath to produce a more mobileliquid for easy pouring. Once fluid, it will remain so for several days
2 zinc the reaction is vigorously exothermic, it is very important to cool the flask as soon as the reaction starts. If thetemperature does not rise by itself, warm the mixture gently on a steam bath. The temperature must be watched very carefully. Once the temperature starts to rise, remove the steam bath immediately and...