[kevsim]

I understand many features of organic chemistry, but I am still stumbling with some of the basics.
When there is a chain of carbons and a function group at the end of the chain and a double bond closest to the other end, does the numbering start from the functional group or the opposite end?
Are there precedence’s in numbering the chain?

Also are there any good web sites that could give good detail in what I am trying to say?

kevsim

[Hunter2]

The functional group gives the lowest number.

https://quizlet.com/19020344/iupac-nomenklatur-der-alkohole-flash-cards/

[kevsim]

Hunter2,
Thank you for the information, very much appreciated.

I am still a little confused as there was a question in a pre exam quiz that asked "Which of the following carboxylic acids is paired with its correct IPUC name?
See attachment.

The answer was "A", it did count from the end of the function group but did not specify (1-butonic acid - 2-chloro).
The butonic acid is not mentioned as "1", does this apply to all functional groups at the end of a chain?

kevsim

[Hunter2]

The carboxylgroup is the number 1. It has not be mentioned.

[kevsim]

Hunter2,
Thanks for the prompt reply.
Do you mean the carboxylgroup does not have to mentioned with a reference number?

kevsim

[Hunter2]

Yes, it can but it is not necessary.