Advertisements
Advertisements
Question
Explain the dehydrohalogenation reaction of 2-chlorobutane.
Advertisements
Solution
When 2-chlorobutane is boiled with an alcoholic solution of potassium hydroxide, it undergoes the elimination of the hydrogen atoms from β-carbon and chlorine atoms from α-carbon resulting in the formation of But-2-ene and But-1-ene.
Reaction:

But according to Saytzeff's rule, in dehydrohalogenation reaction, the preferred product is that alkene which has a greater number of alkyl groups attached to doubly bonded carbon atoms.
Hence, But-2-ene is obtained as the major product in the dehydrohalogenation reaction of 2-chlorobutane.
APPEARS IN
RELATED QUESTIONS
from the following pair would undergo SN2 faster from the other?
a. CH3CH2CH2I b. CH3CH2CH2Cl
Complete the following reaction giving major products.
\[\ce{CH3 - CH = CH2 ->[HBr][peroxide] A ->[alc. KOH] B}\]
Complete the following reaction giving major product.
\[\begin{array}{cc}\ce{CH3\phantom{................}}\\
|\phantom{...................}\\
\ce{CH3 - C - CH2 - Cl ->[Na/dry ether] A}\\
|\phantom{...................}\\
\ce{CH3\phantom{................}}
\end{array}\]
Name the reagent used to bring about the following conversion.
Chlorobenzene to biphenyl
Arrange the following in the increasing order of boiling points.
- 1-Bromopropane
- 2- Bromopropane
- 1- Bromobutane
- 1-Bromo-2-methylpropane
Distinguish between SN1 and SN2 mechanism of substitution reaction.
Convert the following:
Benzyl alcohol to benzyl cyanide
Complete the following reaction sequence by writing the structural formulae of the organic compound 'A', 'B' and 'C'.
\[\ce{Isopropyl alcohol ->[\triangle][PBr3] A ->[][NH3 excess] B}\]
Observe the following and answer the question given below.

Can it react by SN1 mechanism? Justify your answer.
Explain. Aryl halides are less reactive than alkyl halides towards nucleophilic substitution reactions.
Explain aqueous alkaline hydrolysis of tert. butyl bromide.
In alkaline hydrolysis of tertiary butyl bromide, ____________.
Which of the following is a primary halide?
Nitroalkanes are obtained in laboratory from primary or secondary alkyl halides by the action of ______.
How many metameric ethers are represented by the molecular formula C4H10O?
Which of the following is FALSE regarding SN2 reaction mechanism?
The SN2 reaction of a compound containing an asymmetric carbon atom always gives ____________.
Write the product formed when alkyl halide reacts with silver nitrite.
Convert the following.
p-Nitrochlorobenzene to p-nitrophenol
With which halogen the reactions, of alkanes are explosive?
Complete the following reaction giving a major product.
\[\begin{array}{cc}
\ce{CH3}\phantom{.................}\\
|\phantom{...................}\\
\ce{CH3 - C - CH2 - Cl->[Na/dry ether]A}\\
|\phantom{..................}\\
\ce{CH3}\phantom{................}
\end{array}\]
Observe the following and answer the question given below:

Comment on the bond length of C-X bond in it.
Complete the following reaction sequences by writing the structural formulae of the organic compounds 'A', 'B' and 'C'.
\[\ce{2-Bromobutan ->[alc. KOH] A ->[][Br2] B ->[][NANH2] C}\]
Complete the following reaction giving major product.
\[\begin{array}{cc}
\ce{CH3}\phantom{...............}\\
|\phantom{..................}\\
\ce{CH3 - C - CH2 - Cl->[Na/dry ether]A}\\
|\phantom{..................}\\
\ce{CH3}\phantom{...............}\\
\end{array}\]
Complete the reaction:
\[\ce{CH3CH2Cl ->[AgCN][alc.\Delta]}\] ?
Which of the following reagent is used for conversion of alkyl halide into nitrile?
