Nomenclature’s problem

[Cortinarius9819]

Hello, sorry for my bad english. I’ve got a problem with an exercise. I’ve got a compound of which the exercise want to know the name. According to the text is 5-ethyl-4,4-dimethyloctane but for me is 4-ethyl-5,5-dimethyloctane. Because ethyl comes first considering the alphabetical order.

CH₃ CH₂CH₂CH₃
| |
CH₃C—CHCH₂CH₃
|
CH₂CH₂CH₃

[Cortinarius9819]

The propyhl is attached to the CH carbon on the right, there’s an error

[ChenBeier]

The whole drawing makes no sense.

5-ethyl-4,4-dimethyloctane

CH₃CH₂CH₂C(CH₃)₂CH(C₂H₅)CH₂CH₂CH₃

https://pubchem.ncbi.nlm.nih.gov/compou ... thyloctane


4=ethyl-5,5-dimethyloctane.

CH₃CH₂CH₂CH(C₂H₅]C(CH₃)₂CH₃CH₂CH₃

Wrong,
Ethyl comes first in both formula name, but the number of the C with the two methyl has to be smaller.

[Cortinarius9819]

Thanks. Could you please explain why the number of the carbon with the two methyl has to be smaller?

[ChenBeier]

It is one of the laws number has to small as possible, especially more substituents are present.