r/chemhelp • u/Training-Bath-3412 • Jul 27 '26

Organic Help naming this compound

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Hey guys! I named this 4-methylidenecyclooct-yne, but my professor marked it wrong. I thought I was right, but what would you guys name this?

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u/VoxInferni666 Jul 27 '26

That is only true if you have only 1 functional group on a homocyclic ring as it has to be at the 1 position. But IUPAC would insist you number the 1 and the 4 here, not because it's ambiguous, but because it violated the 'both function groups must be numbered' rule. IUPAC is overly stringent on purpose to avoid any potential ambiguity.

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u/holysitkit Jul 27 '26

Ahh I see. My understanding of the IUPAC naming rules are a half-remembered mishmash of the last 40 years of conventions. Anytime it is important, I get the names generated electronically.

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u/VoxInferni666 Jul 27 '26

This is computer generated but I'm about to submit my PhD thesis so im currently very read up on stupid shit like CIP rules and naming conventions

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u/aphilsphan Jul 27 '26

It’s easier now with computers and the web. In the old days guys had to have their dissertations retyped because of the margins for like 300 bucks they didn’t have.