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enter image description here

One base is bulkier than the other, that's my observation. How does it affect the product? Could someone please give proper reasoning and the product? Thanks a lot.

P.S. I guess both follow E2

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    $\begingroup$ With methoxide there is a reasonable chance of getting nucleophilic substitution as well as elimination generating a mixture of products. With the much bulkier t-butoxide this is pretty well non-existent so you only get elimination. $\endgroup$
    – Waylander
    Commented Jun 22, 2017 at 12:31
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    $\begingroup$ It's also possible that the stronger base will abstract the most accessible proton, producing a less stable (kinetic) product. The Zaitsev (thermodynamic) product comes from the least accessible proton in your case. $\endgroup$ Commented Jun 22, 2017 at 12:40
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    $\begingroup$ You might be under E1 conditions and not E2. $\endgroup$
    – Zhe
    Commented Jun 22, 2017 at 14:55

1 Answer 1

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Under $E_2$ reaction conditions, the MeO$^-$ product will be

enter image description here

while the Me$_3$CO$^-$ product will be

enter image description here.

This is due to the bulkiness of Me$_3$CO$^-$ being unable to reach the hydrogen at the substituted carbon so instead it goes to the primary position instead.

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  • $\begingroup$ Do you have references that support this black/white distinction? $\endgroup$
    – Jan
    Commented Jun 23, 2017 at 15:37

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