I was confused by why the following elimination reaction hits only one of the hydrogens instead of both isomers that are possible. Please help me out!

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    $\begingroup$ Why do you think that might be? $\endgroup$ – ralk912 Mar 28 '18 at 2:07
  • $\begingroup$ @ralk shouldn't the bulky base form the less stable product? (i.e. in this case, the non conjugated diene isomer instead) $\endgroup$ – Gaurang Tandon Mar 28 '18 at 4:58
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    $\begingroup$ @GaurangTandon you are misunderstanding the rule. Using a bulky base makes it harder to reach a more hindered proton. There's no much steric hindrance in this molecule that would make that happen $\endgroup$ – ralk912 Mar 28 '18 at 5:05

Conjugated dienes are significantly favorable to non-conjugated dienes (because of delocalization and hybridization, etc.), so this will be the major product. It is not to say that the other reaction cannot happen, but that a combination of factors leads to that product being major. All of chemistry occurs in an equilibrium of some degree, and the reaction above will become most stable in conjugated diene form.


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