Question

What is name of this according to the IUPAC:
a benzene that has an ethyl group on an its carbon , and a double methyl group on another carbon ?
thanks

Answer 1

You can't have that without having a 5-valent carbon and that isn't allowed.

Answer 2

Yes , that's quite right , I actually meant a hexane that has an ethyl group on an its carbon and a double methyl group on another carbon ?
with my best respects

Answer 3

First, the name depends upon where the groups are located. If that is a straight chain hexane, then the ethyl group is named first followed by the number and dimethyl as in
3-ethyl-2,2-dimethyl hexane.
Here is a well illustrated site.
http://www.kentchemistry.com/links/organic/orgonaming1.htm