English
Karnataka Board PUCPUC Science 2nd PUC Class 12

How will you bring about the following conversion in not more than two steps? Ethanol to 3-Hydroxybutanal

Advertisements
Advertisements

Questions

How will you bring about the following conversion in not more than two steps?

Ethanol to 3-Hydroxybutanal

How will you convert the following:

Ethanol to 3-Hydroxybutanal

Chemical Equations/Structures
Advertisements

Solution 1

\[\begin{array}{cc}
\phantom{...............................................................}\ce{OH}\\
\phantom{.............................................................}|\\
\ce{\underset{Ethanal}{CH3 - CH2 - OH}->[Mild oxidation][KMnO4/dil.H2SO4]\underset{(Two molecules)}{\underset{Acetaldehyde}{CH3 - CHO}}->[dil.OH-][warm]\underset{3-Hydroxybutanal}{CHO - CH2 - CH - CH3}}\
\end{array}\]

shaalaa.com

Solution 2

\[\begin{array}{cc}
\phantom{....................................}\ce{OH}\\
\phantom{..................................}|\\
\ce{CH3CH2OH ->[PCC] CH3CHO ->[dil NaOH][Aldol condensation] \underset{3-Hydroxybutanal}{CH3 - CH - CH2 - CHO}}
\end{array}\]

PCC = Pyridinechlorochromate

shaalaa.com
  Is there an error in this question or solution?
Chapter 8: Aldehydes, Ketones and Carboxylic Acids - Exercises [Page 256]

APPEARS IN

NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 8 Aldehydes, Ketones and Carboxylic Acids
Exercises | Q 8.15 (iii) | Page 256

RELATED QUESTIONS

How will you convert ethanal into the following compound?

But-2-enal


Write structural formulas and names of four possible aldol condensation products from propanal and butanal. In each case, indicate which aldehyde acts as nucleophile and which as electrophile.


 Why is alpha (α) hydrogen of carbonyl compounds acidic in nature?


What is substituted imine called?


Explain aldol condensation reaction in detail.


Cannizaro’s reaction is not given by ______.


Which product is formed when the compound  is treated with concentrated aqueous \[\ce{KOH}\] solution?


Which of the following compounds do not undergo aldol condensation?

(i) \[\ce{CH3 - CHO}\]

(ii)  

(iii)  \[\begin{array}{cc}
\phantom{}\ce{O}\\
\phantom{}||\\
\ce{CH3 - C - CH3}
\end{array}\]

(iv) \[\begin{array}{cc}
\phantom{}\ce{CH3}\\
|\phantom{...}\\
\ce{CH3 - C - CHO}\phantom{..}\\
|\phantom{...}\\
\phantom{}\ce{CH3}\\
\end{array}\]


Which of the following conversions can be carried out by Clemmensen Reduction?

(i) Benzaldehyde into benzyl alcohol

(ii) Cyclohexanone into cyclohexane

(iii) Benzoyl chloride into benzaldehyde

(iv) Benzophenone into diphenyl methane


Why is there a large difference in the boiling points of butanal and butan-1-ol?


What product will be formed on reaction of propanal with 2-methylpropanal in the presence of \[\ce{NaOH}\]? What products will be formed? Write the name of the reaction also.


Assertion: The α-hydrogen atom in carbonyl compounds is less acidic.

Reason: The anion formed after the loss of α-hydrogen atom is resonance stabilised.


Assertion: Aromatic aldehydes and formaldehyde undergo Cannizaro reaction.

Reason: Aromatic aldehydes are almost as reactive as formaldehyde.


Which of the following gives aldol con~ensation reaction?


The major product of the following reaction is:


Which of the following compounds will undergo self-condensation in the presence of dilute NaOH solution?


Identify A and B:


When acetaldehyde is treated with dilute NaOH, the following reaction is observed.

\[\begin{array}{cc}
\ce{2CH3 - CHO ->[dil.NaOH] CH3 - CH - CH2 - CHO}\\
\phantom{...............}|\\
\phantom{.................}\ce{OH}
\end{array}\]

  1. What are the functional groups in the product?
  2. Can another product be formed during the same reaction? (Deduce the answer by doing atomic audit of reactant and product).
  3. Is this an addition reaction or condensation reaction?

What is aldol condensation? Explain it with suitable examples.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×