Questions tagged [elimination]
Questions whose main focus is on E1, E2, E1cb, or any other type of elimination reaction.
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Why does alcoholic KOH prefer elimination whereas aqueous KOH prefers substitution?
What is the basic difference between aqueous and alcoholic $\ce{KOH}$? Why does alcoholic $\ce{KOH}$ prefer elimination whereas aqueous $\ce{KOH}$ prefers substitution?
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Why are two three-membered rings preferred to a single five-membered ring in the reaction of a dihalide with alcoholic KOH?
The given answer is 1,1-dicyclopropylmethanone:
Step 1 is abstraction of acidic H by the strong base. Then, there's surely going to be anchimeric assistance. But there can be two places where the ...
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What will be the product when 3,4-dibromocyclohexene is reacted with sodium followed by heating with selenium?
I'm tutoring few Class 12 students for their chemistry exams. I'm stuck with few problems. I don't know, if the key is wrong or I am wrong.
According to me product (A) must be the cyclic diene, ...
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Rearrangement with sodium iodide (ring opening)
I'm not able to figure out the mechanism for this reaction. I don't see how sodium iodide in acetone could lead to rearrangement, and surprisingly ring opening!
What is this reaction called, if it ...
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Why does treatment of a geminal dihalide with sodium amide lead to an alkyne and not an allene?
I've come across the following problem in Klein's Organic Chemistry, 2nd edition:
However, I'm a little bit confused about why the terminal alkyne is produced. I believe that an allene should be ...
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Does (2-fluoroethyl)benzene undergo elimination via E1cb or E2?
I have seen in two different sources claiming that $\ce{PhCH2CH2F}$ gives styrene $\ce{PhCH=CH2}$ when treated with alcoholic $\ce{KOH}$, but one source suggests an E1cb mechanism, while the other ...
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What is the major product in the reaction of 2,3-dichlorobutane with sodium amide in liquid ammonia?
I am not able to decide which among 1,3-butadiene and 2-butyne is the major product of this reaction. Will there be even a major product out of the two or will there be a mixture?
According to me, ...
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How does Hofmann elimination work in this reaction?
In my Chemistry class, we were given this question to solve, and I'm not sure I fully understood the solution.
I understand that since the substrate is bulky, Saytzeff elimination can't happen, so it ...
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Determining if the product would be cis or trans after an anti elimination on fischer projections
I find these kind of problems really confusing for some reason, but I saw a way on the web and tried doing it that way:
I considered the basic Fischer operations (Vertical: Below the plane of paper, ...
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Use of aqueous KOH and alcoholic KOH in dehydrohalogenation reactions [duplicate]
What is the difference between aqueous KOH and alcoholic KOH? How do they react differently in dehydrohalogenation?
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Reaction of conjugated alkene with KNH2
I could not think of this reaction fitting into any of the reactions I know except the aryne mechanism. And hence I came up with the following mechanism after seeing the answer (which I've written in ...
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Dehydration of primary alcohols without a β-hydrogen
What happens in dehydrations of primary alcohols (in presence of acid catalyst at high temperatures) which don't have a β-hydrogen?
For example, in the case of neopentyl alcohol, will it dehydrate as ...
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Mechanism of reaction of ketones with isoalkanes under conc. sulfuric acid and heat
Taken from the book of GOC by Dr. O.P Tandon, Himanshu Pandey, Dr. A.K. Virmani,
Can anyone elaborate on the mechanism?
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When is Zaitsev product formed in pyrolytic elimination reaction?
I recently came across a problem of choosing which product to be made in case of pyrolytic elimination reactions. I was taught that usually Hoffman products are formed in such reactions. For e.g.:
In ...
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Elimination of bromine with sodium iodide and electrocyclization
I've been trying to solve the following reaction scheme for a while now and I am having trouble especially with the products E and F.
For product D I got the following, but I'm unsure about ...
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