This certainly occurs, but it leads nowhere since the hydrate is present in simulation reduction fillon urssaf very small quantities at equilibrium for ketones and most aldehydes.
Experiments have shown that there are many such reagents, but one which is commonly and effectively used for this purpose is chromic acid (H2CrO4).
Its a necessary agent for the oxidation process to proceed.
There are important areas of biochemistry (photosynthesis, oxidative phosphorylation) where this symbolism for oxidation and reduction is very useful, but for most of organic chemistry where molecules have many atoms, keeping track of oxidation levels this way is cumbersome and not very useful.The copper(II) cation is reduced as it gains electrons.This time we'll look at oxidations and reductions of carbonyl groups and at the acidity of the alpha hydrogen atom.Loss of electrons, one way to define oxidation is with the reaction in which a chemical substance loses electrons in going from reactant to product.Now to consider a mechanism.Two important ones are sodium borohydride (NaBH4) and lithium aluminum hydride (LiAlH4).Their use is illustrated in the following two examples.
We can pick out several important features of this reaction from this example.
The oxidizing agent accepts the electrons from the chemical species that is being oxidized.
An alternative view is to describe oxidation as the losing of electrons and reduction as the gaining of electrons.
In the latter case, lithium aluminum hydride is itself highly reactive with water, so the water is added after the lithium aluminum hydride has reacted.
Reactions where the gain of oxygen is more obvious than the gain of electrons include combustion reactions ( burning ) and the rusting of iron.Our mechanism must account for the formation of a carbon-bromine bond and an oxygen-hydrogen bond (in water) and the cleavage of a carbon-hydrogen bond (alpha) and a bromine-bromine bond.Reactivity is restricted to the C-H bond on a carbon directly to the carbonyl carbon.Second, we notice that there is no reaction at the beta-C-H bonds.Since there is no carbon-carbon bond breaking which occurs in these reactions, we might expect that these reagents would also reduce ketones to alcohols.Notice that either resonance structure can be used to deliver the needed pair of electrons to make the carbon-bromine bond.What is it about an enolate ion which allows it to be made at all.One example in which this approach is of value is in the high temperature reaction of lead dioxide.With this information and the addition of a Grignard reagent as a pattern, we can arrive at the following mechanism for the reduction of an aldehyde by sodium borohydride.Here's an example of such a reaction.