In E2 reaction, there is more than one product. According to Zaitsev’s rule – “The alkene formed in greatest amount is the one that corresponds to removal of the hydrogen from the β-carbon having the fewest hydrogen substituents.” (Wikipedia)

Now, my question is, how can the base effect the percentage of the minor and major products? Does a stronger base give us more major product and vice versa?

The particular question I’m trying to solve is: In the E2 reaction of 2-bromo-2,3-dimethyl butane, which base would give more of the minor product and which of the major product? the four given bases

  • $\begingroup$ Could you provide the base strength for the compounds? $\endgroup$
    – LDC3
    May 24, 2015 at 15:51
  • $\begingroup$ What do you mean? that's all the data I've got $\endgroup$
    – ems
    May 24, 2015 at 16:04

1 Answer 1


It will be more difficult for sterically hindered bases to remove the proton of the β-carbon having the fewest hydrogen substituents, since this carbon atom has more bulky groups around it compared to the the others. So base 3, being the less hindered base, will provide a higher percentage of the major Zaitsev’s product and base 2 will provide a higher percentage of the minor product compared to the other bases.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.