I was required to find the products on heating the hydroxide of; enter image description here

Now it's easy enough to find the answer; Hoffman elimination isn't going to happen from the methyl, and the n-propyl doesn't have $\beta$-hydrogens as acidic as that of the ethyl. It doesn't feel like the hydrogens in the ring are more acidic, either, so the product involves ethene. Simple enough.

But this lacks rigor. How do I actually evaluate the inductive effect on the $\beta$-carbons on the ring? If I have to compare it to some other fragment less obvious to win than ethyl, where do I start counting the carbons that inductively push electron density onto the $\beta$-carbons on the ring?

  • $\begingroup$ Is that a boat conformation? In any case I interpret the drawing as a trans methyl amino cyclohexane. That means the methyl and amino groups are both equatorial and not optimally arranged for a Hoffman elimination in solution. I have no idea of the physical arrangement with the hydroxide ion in a melt. If a boat configuration is intended the ring is set up for a syn elimination. This is best settled by finding the publication if this has been run or by synthesizing the compound if it hasn't. $\endgroup$
    – jimchmst
    Commented May 4, 2021 at 6:09
  • $\begingroup$ @jimchmst: isn't cis-trans nomenclature for unsaturated systems? $\endgroup$
    – harry
    Commented May 4, 2021 at 6:55
  • $\begingroup$ It is also pertinent to saturated simple ring compounds $\endgroup$
    – jimchmst
    Commented May 5, 2021 at 17:07


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