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Hello. I am confused on how the substituents were numbered in this problem. I got 2,3,4,4-tetramethylcyclohexene as the name, but the solution has 1,5,5,6-tetramethylcyclohexene as the answer. Why is it numbered this way? I thought you want to minimize the numbering (lowest to the double bond), so that the substituents are the smallest numbers possible?
The double bond does get priority but the correct way to number it also gives a lower number for the first substituent than how you numbered it (1<2) while still having the double bond at carbon 1. Usually, it's better to start numbering on the carbon that has a substituent attached AND has a double bond, which is why the lowest number for the first substituent can be obtained by numbering counterclockwise from the carbon that has a methyl group attached and has the double bond. Although this gives larger numbers for the other substituents, we pick the numbering that gives the first lowest number, and 1 is smaller than 2.
The set (1,5,5,6) is better than (2,3,4,4) because 1 < 2. Compare the point of first difference and then forget about the rest of them. Only if the first numbers have a tie, would you move to compare the 2nd ones, etc.
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