Cannizzaro Reaction

13 October, 2014 / by SK / in Reactions

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General Characteristics

Upon treatment with strong bases (e.g. in aqueous NaOH) and heating, non-enolizable aldehydes undergo redox disproportionation to give corresponding alcohols and carboxylic acids in 1:1 ratio.

The crossed Cannizzaro reaction between two different aldehydes is difficult and a statistical mixture of four products is usually expected. However, when one of the aldehydes is formaldehyde, it reacts as a reducing agent more preferentially, giving the alcohol derived from the other aldehyde in good yield.

The Cannizzaro reaction doesn’t work well for enolizable aldehydes due to competing aldol reaction.

General References

・Cannizzaro, S. Ann. 1853, 88, 129. doi:10.1002/jlac.18530880114
・List, K.; Limpricht, H. Ann, 1854, 90, 190. doi:10.1002/jlac.18540900211
・Geissman, T. A. Org. React. 1944, 2, 94.