In a dry
1-l. round-bottomed flask are placed
100 g. (0.82 mole) of powered nicotinamide and
100 g. (0.70 mole) of phosphorus pentoxide. The flask is stoppered and shaken to mix the two powders. It is then connected by means of a
10-mm. i.d. tube to an 80-cm. air condenser arranged for distillation. A
125-ml. Claisen flask immersed in an
ice-salt bath is used as the
receiver (Note
1). The pressure is reduced to 15–20 mm., and the mixture is heated with a large free flame of a high-temperature burner (such as a Fisher or Meker type). The flame is moved about freely to melt the material as rapidly as possible, and then the mixture is heated vigorously until nothing more comes over or until foam reaches the top of the flask (15–20 minutes). The apparatus is allowed to cool (Note
2), and the product is rinsed out of the tube and condenser with
ether (Note
3). The
ether solution is added to the distillate, the
ether is distilled on a
steam bath, and the product is distilled at atmospheric pressure using an air condenser. The yield of
nicotinonitrile, boiling at
205–208° and melting at
50–51°, is
71–72 g. (
83–84%).