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Topic: Difference in nomenclature?  (Read 2716 times)

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Offline Agent-X

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Difference in nomenclature?
« on: July 22, 2009, 05:06:04 PM »
I don't understand why these two have different names.
I don't understand the locant positioning.

I have grasped many basics of nomenclature, but this mystifies me.

Am I to understand that the 2-cyclo... is because it's on the second carbon reaching toward the cyclogroup?
And the other is 1-cyclo, because the cyclo is attached to the first carbon that would lead outside of the functional group?

edit: it's suppose to be 1-cyclohexylmethyl
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Offline Schrödinger

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Re: Difference in nomenclature?
« Reply #1 on: July 25, 2009, 02:43:04 PM »
Actually, the locant number depends on the group that is to the attached to the ethyl group.

In the first pic, if it is a functional group that is linked to the dashed line, then since that has to be given the lower locant number due to more preference, the cyclohexyl group is given lower locant number (it is just a substituent).

In the second pic, there is no problem, I presume.

 
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