Using E-Z Notation, name this molecule.

Could it be 5-chloro-2-methylheptane

No, it's definitely an -ene because of the double bond.  Using EZ-notation (E for trans and Z for cis), this molecule would be named (E) 4-chloro-5-isopropyl-oct-4-ene

E means the higher priority groups are on opposite sides of the double bond, 8 is the longest carbon chain with the double bond (octene), and the 4th carbon has the double bond.  Also, because chloro is alphabetically before isopropyl, you'd number left to right since it's possible to go both ways.

way off, sorry. That'll be my last chemistry answer.

Actually, correct answer is (E) 4-chloro-5-isopropyloct-4-ene

Dashes only between numbers and words; commas between numbers.  Sorry.

Post Merge: 10 years ago

@padre I'm not always 100% when I answer either.  Basically just trying to help however we can.

hello

Thank you very much!! Just for clarification, we had this as a test question and that very structure was given as the answer for the following name: E-4-chloro-2-methyl-3-propyl-3-heptene

I knew that structure could not have been E-4-chloro-2-methyl-3-propyl-3-heptene because the longest carbon chain including the alkene double bond is 8 carbons long! I think I should bring this up to my instructor because it is impossible to draw E-4-chloro-2-methyl-3-propyl-3-heptene without drawing octene and hence the question is wrong.

I am 100% sure my nomenclature is correct. Assuming the picture is drawn correctly, I'd alert the professor. There are definitely 8 carbons in the longest chain including the double bond. I taught MCAT G-chem and O-chem and I scored perfect on both the DAT & PCAT O-Chem sections, so I'm not just spouting off at the mouth. Not trying to be that guy but I'm just saying I'm confident you are correct to question that question.

Post Merge: 10 years ago

Also, as an aside, were it heptene, it would be Z (cis-). Or it could hypothetically be E-hexene, but neither are correct under any accepted naming conventions.

Post Merge: 10 years ago

Just to clear up what I meant above, were it heptene, the propyl and chloro groups would be on the same side (Z)

Doctor-2-B,

Thank you for your help and input it is greatly appreciated! The picture is definitely drawn the way the answer was given as I literally used a screenshot of the answer. When I was trying to draw it I kept coming up with octene so I checked the answer and the structure provided was given the name 'E-4-chloro-2-methyl-3-propyl-3-heptene'. I knew this could not be correct as I spotted the 8 carbon chain first out of everything. I will definitely bring this up (politely of course) with my instructor because the students who got this question wrong should be given an additional few marks as it is impossible to draw that structure and still call it 'heptene'.

Glad I could confirm your suspicions. Let us know how this works out. If this professor continues to assert that this is heptene, please let me know his rationale.

Will do! Thanks again to you and anybody else who helped on this question!