What alkenes would give only an aldehyde with four carbons as a product of oxidative cleavage?

1 Answer
Jan 13, 2015

The six possible alkenes are the cis and trans isomers of oct-4-ene, 2,5-dimethylhex-3-ene, and 1,2-di(cyclopropyl)ethene.

Oxidative cleavage of an alkene is the conversion of the alkene carbons into separate carbonyl groups.

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We can work backwards from the products and figure out what the alkene must have been.

If the product was RCHO, the alkene must have been RCH=CHR.

There are three 4-carbon aldehydes:

Butanal
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2-Methylpropanal
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Cyclopropanecarboxaldehyde
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From these, we can work backwards and say that the starting material must have been the E or Z isomer of

Oct-4-ene
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2,5-Dimethylhex-3-ene
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or

1,2-Di(cyclopropyl)ethane
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So there are six possible alkenes that give only a four-carbon aldehyde by alkene cleavage.