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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
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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
A compound 'A' of molecular formula C2H3OCl undergoes a series of reactions as shown below. Write the structures of A, B, C and D in the following reactions :
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- Methanal
- 2-Methylpentanal
- Benzaldehyde
- Benzophenone
- Cyclohexanone
- 1-Phenylpropanone
- Phenylacetaldehyde
- Butan-1-ol
- 2, 2-Dimethylbutanal
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Complete the synthesis by giving missing starting material, reagent or product.
\[\begin{array}{cc}
\ce{C6H5CHO}\phantom{............}\\
\phantom{........}\ce{+\phantom{......}\ce{->[dil.NaOH][\Delta]}}\phantom{...}\\
\ce{CH3CH2CHO}\phantom{............}
\end{array}\]
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\[\ce{CH3CHO ->[(i) CH3MgBr][(ii) H2O] (A) ->[H2SO4, Δ] (B) ->[Hydroboration oxidation] (C)}\]
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) \[\begin{array}{cc}
\phantom{}\ce{CH3}\\
|\phantom{...}\\
\ce{CH3 - C - CHO}\phantom{..}\\
|\phantom{...}\\
\phantom{}\ce{CH3}\\
\end{array}\]
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The major product of the following reaction is:
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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?
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- Is this an addition reaction or condensation reaction?
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