7.2: The Reactions of Exp. 35

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Refer to pages 289-290 of your textbook.

It is clear now how the oxidation-reduction scheme of p. 289 is being used here to illustrate the concept experimentally. An alcohol (borneol) is being oxidized into a ketone (camphor). A subsequent reduction takes us back to another alcohol (isoborneol), which is an isomeric form of the original.

The oxidizing agent in the first step is sodium hypochlorite, which is present in commercial bleach as an aqueous solution. in fact, the reaction can be performed using bleach, but it must be relatively fresh. Sodium hypochlorite decomposes in water slowly, and using old bleach could introduce a source of error in the experiment.

The reducing agent in the second step is sodium borohydride, which will be used in alcoholic solution. Again, sodium borohydride reacts with alcohols slowly. Therefore it is important that the solution be freshly prepared. If you monitor, your reactions by IR you'll have a good indicator of the effectiveness of the conversions, and therefore of the quality of the reagents used. Ineffective reagents can result in incomplete conversions, which will show the presence of starting material in the IR spectrum of products.