E2 Reaction - What determines the major products? (Reaction inside)

[manohman]

So I thought that the major determinants of product formation for E2 were:

1) LG and Hydrogen to be deprotonated (taken by the base) must be anti
2) Once that was fulfilled you went for the most stable product - more substituted Alkene product is more stable.

But a question I had said that if the base is bulky, but strong, it will attack the least substitued carbon forming the Hoffman Product.

So the answer here is C apparently. Can someone clarify when bulkiness of the base takes precedence over forming the most stable product? here thats the difference between forming a more substitued alkene product (# 2 vs #3)

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[Hadi7183]

Reactions involving t-butoxide are kind of special. Check this link: http://www.masterorganicchemistry.com/2011/10/29/reagent-friday-kotbu/

 

[cjcarter]

You have steric hindrance with a secondary alkyl halide so a bulky base will give the Hofmann product. Same for tertiary alkyl halides. If you had a smaller base, like ethoxide or something, you would get the Zaitsev product. Bulky bases will form the more stable alkene with primary alkyl halides since it has room to abstract the proton.