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Naming ketone q

This is the structure:
CH3C=OCH3, this is propanone. Why does it have 'propan' with it when there's a double bond, shouldn't it have 'ene' in somewhere? Why is there no number to indicate where the double bond is? I think it'd make more sense if it was prop-2-ene-one or something.
Original post by Magenta96
This is the structure:
CH3C=OCH3, this is propanone. Why does it have 'propan' with it when there's a double bond, shouldn't it have 'ene' in somewhere? Why is there no number to indicate where the double bond is? I think it'd make more sense if it was prop-2-ene-one or something.


It doesn't have a double bond between two carbon atoms (the requirement for an alkene), it has a carbonyl group, C=O.

The longest chain is three carbons = prop-
The functional group = carbonyl (in the middle of the chain), suffix -anone.

The name is propanone

You might like to take a look at this interactive on organic homologous series
(edited 10 years ago)
Original post by Magenta96
This is the structure:
CH3C=OCH3, this is propanone. Why does it have 'propan' with it when there's a double bond, shouldn't it have 'ene' in somewhere? Why is there no number to indicate where the double bond is? I think it'd make more sense if it was prop-2-ene-one or something.


Ketones have a C=O group and end in the suffix -one.

3 Carbons = propan so overall, propanone.

The reason there is no number is because the middle is the only position the C=O bond could be in for it to be a ketone. If it was on the first or third carbon it would be an aldehyde instead.

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