Some addition-elimination reactions of aldehydes and ketones

There are other examples of processes that replace the C=0 bond with a C=C bond. These reactions will be discussed primarily in Part B, Chapter 2. 

The hydrolysis of simple imines occurs readily in aqueous acid, and has been studied in great detail by kinetic methods. The precise mechanism is a function of the reactant structure and the pH of the solution. The overall mechanism consists of an addition of water to the C=N bond, followed by expulsion of the amine from a tetrahedral intermediate.  

The relative rates of the various steps are a function of the pH of the solution and the basicity of the imine. In the alkaline range, the rate-determining step is usually 

Complete understanding of the shape of the curves in Fig. 8.1 requires a kinetic expression somewhat more complicated than we wish to deal with here. The nature 

In the alkaline region, the rate is pH-independent. In this region, the ratedetermining step is attack of hydroxide ion on the protonated imine. The concentration of each of these species is pH-dependent, but in opposite, compensating, ways, and the overall rate is therefore pH-independent in the alkaline range (see problem 5). 

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Scheme 8.2. Some Addition-Elimination Reactions of Aldehydes and Ketones...

Some addition-elimination reactions of aldehydes and ketones... 

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