Permanganate Oxidation Research Paper

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A redox process involves electron transfer between an oxidant and a reductant. Permanganate, an important oxidant in many or￾ganic and inorganic redox reactions, involves the Mn(VII) entity, which is renowned for its versatility. The permanganate oxidation process is eco-friendly and has gained importance in green chem￾istry. Chemical oxidation is full of illustrations of the use of many uni-atomic metallic ions as oxidants, e.g., Ag(I), Fe(III), Ce(IV),
Cr(VI), Mn(VII), etc., and some large biological oxidants like FAD,
NADP, etc. Permanganate, however, in various homogeneous and heterogeneous media, as well as on solid supports and in solvent￾free conditions, provides excellent results when used in a large number of oxidation processes.

Consequently, at high pH values, it is sometimes difficult to ascertain whether an oxidation is proceeding via a one- or a two-electron process.
Solutions of MnO4 are intrinsically unstable, decomposing slowly, but observably, in an acid medium (Eq. 1):
4MnOL
4 D4HD/3O2D2H2OD4MnO2 (1)
In neutral or slightly alkaline solutions in the dark, de￾composition is immeasurably slow. It is, however, catalyzed by light.
In basic solution, permanganate functions as a powerful oxidizing agent (Eo¼þ1.23 V) (Eq. 2):
MnOL
4 D2H2OD3e/MnO2D4OHL (2)
In very strong base and with an excess of MnO4
, however, manganate ion is produced (Eo¼þ0.56 V) (Eq. 3):
MnOL
4 De/MnO2L
4 (3)
In acid solution, permanganate is reduced to Mn2þ by an excess of reducing agent (Eo¼þ1.51 V) (Eq. 4):
MnOL
4 D8HDD5e/Mn2DD4H2O (4)
Since MnO4 oxidizes Mn2þ (Eo¼þ0.46 V), the product in the presence of an excess of permanganate is MnO2 (Eq. 5):
2MnOL
4 D3Mn2DD2H2O/5MnO2D4HD (5)
The highest oxidation state of manganese corresponds to the total number of 3d and 4s electrons. This VII-state occurs in the oxo
compounds

A few compounds of Mn(V) species are frequently postulated as intermediates in the reduction of permanganates.
Although Mn(II) is the most stable oxidation state, it is quite readily oxidized in alkaline solution.
Permanganate is a versatile oxidizing agent and is used for studying the oxidation kinetics of many organic substrates. The mechanisms for different organic substrates suggested by various authors are not similar, indicating that a variety of mechanisms are possible, depending upon the nature of the reactive manganese species, the reaction environment and the nature of the substrate.
2. Oxidation of alkenes and their derivatives in aqueous media The oxidation of carbon–carbon double bonds by permanganate ion is an important and well-known reaction in organic chemistry, in a mechanistic as well as a synthetic prospective. Under alkaline conditions, olefins are converted into the corresponding diols in good yield,3,4 while in neutral or slightly basic solutions a-hydroxy ketones are produced.4,5 These reactions are always accompanied by a certain amount of C–C bond cleavage6 and, under acidic con￾ditions, the cleavage products predominate.7,8
Aqueous potassium permanganate was used originally for