Under hot, concentrated KMnO4, alkenes undergo oxidative cleavage to yield which products?

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Multiple Choice

Under hot, concentrated KMnO4, alkenes undergo oxidative cleavage to yield which products?

Hot, concentrated KMnO4 breaks the C=C bond and fully oxidizes the two fragments that were once part of the double bond. What those fragments become depends on how many hydrogens are on each double-bond carbon. If a carbon carries at least one hydrogen, that fragment is oxidized to a carboxyl group (–CO2H). If a carbon has no hydrogens (it is fully substituted by other carbon groups), oxidation stops at a carbonyl on that fragment, giving a ketone. So, for an unsymmetrical alkene, you can end up with one side forming a ketone and the other side forming a carboxylic acid. This reflects the range of possible oxidative outcomes under these vigorous conditions, unlike milder cases that yield a diol or other products. Cold, dilute KMnO4 would give a vicinal diol instead, while strong conditions push toward complete cleavage to carbonyl-containing fragments.

Hot, concentrated KMnO4 breaks the C=C bond and fully oxidizes the two fragments that were once part of the double bond. What those fragments become depends on how many hydrogens are on each double-bond carbon. If a carbon carries at least one hydrogen, that fragment is oxidized to a carboxyl group (–CO2H). If a carbon has no hydrogens (it is fully substituted by other carbon groups), oxidation stops at a carbonyl on that fragment, giving a ketone.

So, for an unsymmetrical alkene, you can end up with one side forming a ketone and the other side forming a carboxylic acid. This reflects the range of possible oxidative outcomes under these vigorous conditions, unlike milder cases that yield a diol or other products. Cold, dilute KMnO4 would give a vicinal diol instead, while strong conditions push toward complete cleavage to carbonyl-containing fragments.

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