alkene cleavage with KMnO4

[zeuscorey2]

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kaplan says:

-if it's cold & dilute it will yield 1,2 diols
-if it is hot and basic it will yield 2 carboxylic acids if the alkene is not terminal, or 1 carboxylic acid and CO2 if monosubstituted terminal, or ketones if disubstituted terminal.

but

http://www.wikipremed.com/03_organicmechanisms.php?mch_code=030202_080

says potassium permanganate forms a vicinal diol. Oxidative cleavage by permanganate in neutral or acidic conditions yield carbonyl compounds

can someone clarify this in terms of temperature/acidic/basic?

 

[DoCt0rPeTe]

kaplan says:

-if it's cold & dilute it will yield 1,2 diols
-if it is hot and basic it will yield 2 carboxylic acids if the alkene is not terminal, or 1 carboxylic acid and CO2 if monosubstituted terminal, or ketones if disubstituted terminal.

but

http://www.wikipremed.com/03_organicmechanisms.php?mch_code=030202_080

says potassium permanganate forms a vicinal diol. Oxidative cleavage by permanganate in neutral or acidic conditions yield carbonyl compounds

can someone clarify this in terms of temperature/acidic/basic?

A vicinal diol is the same as a 1,2 diol. That is under cold and dilute conditions. The mechanism is different when heat is added, and oxidation occurs, yielding the carbonyl compounds as shown.