When to use Z vs. E?

[sarathornburgh1b]

How do we know when we need to include Z vs. E in a cycloalkene? In some of the posted problem sets it includes them and in some it does not.

[Sakina_Qadir_3K]

In most cases, I believe you use Z when it is "cis" (which means on the same side) and use E when it is "trans"(which means on opposite sides). Hope that helps!

[Manpreet Singh 1N]

More specifically Z is used when the high priority groups are on the same side and E is when the high priority are on the opposite side. The high priority group is determined by atomic number

[Mana_Sheykhsoltan_1A]

What if two substituents are on one side and one subsistent is on the other side? Would it be cis or trans? I understand when you are only looking at two substituents, but how do you differentiate cis from trans when there are more than two substituents?

[ChiragThadaniDis2M]

What if two substituents are on one side and one subsistent is on the other side? Would it be cis or trans? I understand when you are only looking at two substituents, but how do you differentiate cis from trans when there are more than two substituents?

You will first have to determine the priority of the two substituents that are on the same side. The constituent that has more priority will be compared to the constituent on the other carbon and based on the location, you can determine if it is cis or trans.