Diacetone alcohol dissociation

Acetone and diacetone alcohol are in equilibrium with each other. The speed of both reactions is greatly accelerated by the presence of a base. The equilibrium mixture contains only a few per cent of diacetone alcohol but the dissociation of diacetone alcohol to acetone proceeds so slowly in the absence of barium hydroxide that it is possible to increase the concentration to 80 per cent by this procedure. 

In this case however the position of equilibrium is not in favour of the condensation product (which rapidly dissociates into the ketone in the presence of base), and a technique has to be employed which continuously removes the ketol product, as it is formed, from the presence of base. A satisfactory procedure for converting acetone into diacetone alcohol is described in Expt 5.213. The dehydration step to give mesityl oxide is subsequently effected by the presence of a trace of iodine. 

Bell, R.P. and Prue, J.E. (1949) Reaction-kinetic investigations of the incomplete dissociation of salts. Part I. The decomposition of diacetone alcohol in solutions of metallic hydroxides. J. Chem. Soc., 362-369. 

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