Advertisements
Advertisements
प्रश्न
Write the mechanism of the following reaction :
उत्तर १
Primary alcohols such as ethanol react by SN2 mechanism with halogen acid such as HBr as follows:
उत्तर २
This is a nucleophilic substitution reaction. It follows SN2 mechanism. The mechanism is as follows:
1) Protonation of hydroxyl group to make it a good leaving group.
2) Displacement of water molecule by bromide ion to form alkyl bromide.
APPEARS IN
संबंधित प्रश्न
Give the equation of the following reaction:
Oxidation of propan-1-ol with alkaline KMnO4 solution.
When 3-methylbutan-2-ol is treated with HBr, the following reaction takes place:
\[\begin{array}{cc}
\phantom{.......................}\ce{Br}\\
\phantom{......................}|\\
\ce{CH3 - CH - CH - CH3 ->[HBr] CH3 - C - CH2 - CH3}\\
\phantom{.}|\phantom{......}|\phantom{......................}|\phantom{........}\\
\phantom{}\ce{CH3}\phantom{...}\ce{OH}\phantom{...................}\ce{CH3}\phantom{.....}
\end{array}\]
Give a mechanism for this reaction.
(Hint: The secondary carbocation formed in step II rearranges to a more
stable tertiary carbocation by a hydride ion shift from 3rd carbon atom.)
Which of the following are used to convert RCHO into RCH2OH?
(i) H2/Pd
(ii) LiAlH4
(iii) NaBH4
(iv) Reaction with RMgX followed by hydrolysis
Cyclohexene is best prepared from cyclohexanol by which of the following:
The process of converting alkyl halides into alcohols involves ______.
Name the factors responsible for the solubility of alcohols in water.
Explain why is OH group in phenols more strongly held as compared to OH group in alcohols.
Ethers can be prepared by Williamson synthesis in which an alkyl halide is reacted with sodium alkoxide. Di-tert-butyl ether can’t be prepared by this method. Explain.
Assertion: Bond angle in ethers is slightly less than the tetrahedral angle.
Reason: There is a repulsion between the two bulky (–R) groups.
Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.
