Numbering the Carbon
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Numbering the Carbon
How do you know which Carbon is carbon one, for example on 1-ethoxy-3-methylpentane? why is the carbon to the left of the oxygen 1 and not the one on the right? also, if the carbon to the left of the oxygen is the first carbon, why is the carbon to the right also a 1 when naming it "1-ethoxy"?
Re: Numbering the Carbon
Because the other option is 5-ethoxy-3-methylpentane which uses higher numbers.
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Re: Numbering the Carbon
What I do is, I right them out both ways and then I add the number of Carbons and chose the one with the least. For example, 1+3 is 4 while 5+3 is 8. So the first one was the correct one because 4 is smaller than 8. Hopefully that helps a little.
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Re: Numbering the Carbon
Manuel Gonzalez_1L wrote:What I do is, I right them out both ways and then I add the number of Carbons and chose the one with the least. For example, 1+3 is 4 while 5+3 is 8. So the first one was the correct one because 4 is smaller than 8. Hopefully that helps a little.
I thought that we aren't supposed to use the "sum rule" to decide numbering.
Re: Numbering the Carbon
Do not EVER take the sum of numbers.
1,3 is preferable to 3,5 for the following reason: 1 is less than 3 (and that's it. If the first numbers were tied, then you move on to compare the second ones)
Taking the sum CAN result in the wrong name.
1,3 is preferable to 3,5 for the following reason: 1 is less than 3 (and that's it. If the first numbers were tied, then you move on to compare the second ones)
Taking the sum CAN result in the wrong name.
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