In a
2-l. round-bottomed flask with ground-glass joint (Note
1) are placed
100 g. (0.82 mole) of powdered nicotinamide (Note
2) and
1 l. of C.P. glacial acetic acid, and the mixture is warmed with occasional shaking on a
steam bath until a clear solution is obtained. To this mixture is added
160 ml. (1.39 moles) of cold 30% hydrogen peroxide. An air condenser is attached to the reaction flask, and the mixture is heated on a steam bath for 3.5 hours.
The reaction mixture is then distilled under reduced pressure (80–100 mm.) (Note
3). After 600–700 ml. has distilled, the mixture is diluted with 150–200 ml. of distilled water and the distillation is continued. The product separates near the end of the distillation, causing somewhat vigorous bumping for a short period. When the bumping has almost ceased, the pressure is reduced to 20 mm. and the distillation continued almost to dryness (Note
4).
The major portion of wet solid is removed from the flask and transferred to a
1-l. Erlenmeyer flask. The remaining solid is washed out with a little distilled water, and the washings are transferred to the flask. The solid is dissolved in the smallest amount of boiling water required, the flask removed from the heat source, and
50 ml. of ethyl alcohol added (Note
5). The flask is allowed to cool slowly, and, after the major portion of the product has separated, the flask is cooled to 5° overnight. The solid is removed by filtration and washed with cold alcohol, then
acetone, and finally
ether. The white, crystalline, air-dried product weighs
82–93 g. (
73–82%), m.p.
291–293° dec. (rapid heating); the compound starts to turn brown at about 280–285° (Note
6).