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प्रश्न
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
उत्तर १
\[\begin{array}{cc}
\phantom{...............................................................}\ce{OH}\\
\phantom{.............................................................}|\\
\ce{\underset{Ethanal}{CH3 - CH2 - OH}->[Mild oxidation][KMnO4/dil.H2SO4]\underset{(Two molecules)}{\underset{Acetaldehyde}{CH3 - CHO}}->[dil.OH-][warm]\underset{3-Hydroxybutanal}{CHO - CH2 - CH - CH3}}\
\end{array}\]
उत्तर २
\[\begin{array}{cc}
\phantom{....................................}\ce{OH}\\
\phantom{..................................}|\\
\ce{CH3CH2OH ->[PCC] CH3CHO ->[dil NaOH][Aldol condensation] \underset{3-Hydroxybutanal}{CH3 - CH - CH2 - CHO}}
\end{array}\]
PCC = Pyridinechlorochromate
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संबंधित प्रश्न
How will you bring about the following conversion?
Ethanal to but-2-enal
What is meant by the following term? Give an example of the reaction in the following case.
Aldol
How will you convert ethanal into the following compound?
Butane-1, 3-diol
Complete the synthesis by giving missing starting material, reagent or product.
\[\begin{array}{cc}
\ce{C6H5CHO}\phantom{............}\\
\phantom{........}\ce{+\phantom{......}\ce{->[dil.NaOH][\Delta]}}\phantom{...}\\
\ce{CH3CH2CHO}\phantom{............}
\end{array}\]
Why is alpha (α) hydrogen of carbonyl compounds acidic in nature?
Write chemical equations of the following reaction :
Benzoyl chloride is hydrogenated in the presence of `"Pd"/(BaSO_4)`
Write a chemical equation for the following reaction:
Propanone is treated with dilute Ba( OH)2.
What is substituted imine called?
Explain aldol condensation reaction in detail.
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) \[\begin{array}{cc}
\phantom{}\ce{CH3}\\
|\phantom{...}\\
\ce{CH3 - C - CHO}\phantom{..}\\
|\phantom{...}\\
\phantom{}\ce{CH3}\\
\end{array}\]
Why is there a large difference in the boiling points of butanal and butan-1-ol?
Compound ‘A’ was prepared by oxidation of compound ‘B’ with alkaline \[\ce{KMnO4}\]. Compound ‘A’ on reduction with lithium aluminium hydride gets converted back to compound ‘B’. When compound ‘A’ is heated with compound B in the presence of \[\ce{H2SO4}\] it produces fruity smell of compound C to which family the compounds ‘A’, ‘B’ and ‘C’ belong to?
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?
Identify A and B from the following reaction:
\[\begin{array}{cc}
\ce{CH3}\phantom{.................}\\
|\phantom{....................}\\
\phantom{}\ce{2CH3 - C = O ->[Ba(OH)2] A ->[Δ] B + H2O}
\end{array}\]
\[\ce{CH3-CH2-CHO ->[dil][alkali] Product}\]
The product in the above reaction is:
Identify A and B:
When acetaldehyde is treated with dilute NaOH, the following reaction is observed.
\[\begin{array}{cc}
\ce{2CH3 - CHO ->[dil.NaOH] CH3 - CH - CH2 - CHO}\\
\phantom{...............}|\\
\phantom{.................}\ce{OH}
\end{array}\]
- What are the functional groups in the product?
- Can another product be formed during the same reaction? (Deduce the answer by doing atomic audit of reactant and product).
- Is this an addition reaction or condensation reaction?
What is aldol condensation? Explain it with suitable examples.
