Qvault Ochem question on E2

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mario0923

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the question is to choose the best reagent for the reaction to make 2-methyl-2-pentene from 2-chloro-2-methylpentane.

according to Qvault, the correct answer is t-But Na and NaOH is a wrong answer
because t-but is a strong base whereas NaOH is a strong base and a strong nucleophile.
t-but will only undergo E2 whereas NaOH will undergo both E2 and Sn2

but I thought t-butO is very bulky so it will produce Hoffmann product which will be 2-methylpentene not 2-methyl-2-pentene..(according to Chad's video on E2 and E1 reactions)

I thought Sn2 will not occur since this is a tertiary carbon.

am I wrong?
 

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Hm, correct me if I'm wrong anyone, but I think t-ButO will always attack E2? At least in the context of DAT. And doesn't this reaction depict E2, not SN2?
 
Oh sorry, I realized that I didn't really answer your question haha ... well I guess since both of them do E2, this question seems to be asking the more basic recognition of the fact that a t-ButO will attack E2. Not sure about the Hoffman
 
t-ButO will always go E2
that is not my question
my question is when t-ButO attacks the bulky molecules like tertiary like in the problem I have asked

my question is where the double bond is going to form
 
but t-ButO is a bulky base so it will not attack the hydrogen of C3 but it will attack the hydrogen of the methyl group so the double bond will form in at the very beginning of the chain (according to my notes...)

this is confusing...
 
that seems to be a mistake in my opinion for the very reason you mentioned. t-butyl is a bulky base and will give the hoffman product rather than the zaitsev.
 
that seems to be a mistake in my opinion for the very reason you mentioned. t-butyl is a bulky base and will give the hoffman product rather than the zaitsev.

So you think my reasoning is correct?
I think Qvault has a lot of mistakes especially in ochem questions..
 
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