Pyridine → Dodecylpyridinium bromide

Participants

Reaction Steps

Dodecyl pyridinium bromide (DDPB) was prepared in a stirred three neck flask (250 ml) fitted with a reflux condenser and a type j thermocouple probe. Heat was supplied by a Glascol mantel controlled with an IR2 digital temperature controller. In each test, 64.2 grams of alcohol, glycol or glycol ether, 20.7 grams of pyridine (0.26 mole) and 65.1 grams (0.26 mole) of 1-bromo dodecane were placed in the flask. The flask was heated with stirring to 85° C. An exotherm was encountered which caused the temperature to rise to about 100° C. The temperature controller was adjusted to 95° C. and this temperature was maintained throughout the preparation. At set times, samples were drawn and the bromide concentration was determined on a Mettler Model 25 autotitrator using the chloride specific ion silver nitrate method. The reaction was terminated when the bromide concentration reached 96% of the theoretical value.

Provenance & Evidence