Advertisements
Advertisements
प्रश्न
Which of the following compounds will undergo self-condensation in the presence of dilute NaOH solution?
विकल्प
C6H5CHO
CH3CH2CHO
(CH3)3C – CHO
H – CHO
उत्तर
CH3CH2CHO
Explanation:
Aldehydes and ketones having at least one α-hydrogen undergo a reaction in the presence of dilute alkali as catalyst to form β-hydroxy aldehydes (aldol) or β-hydroxy ketones (ketol), respectively. This is known as Aldol reaction.
Because of the presence of α-hydrogen, CH3CH2CHO undergoes an aldol reaction.
APPEARS IN
संबंधित प्रश्न
How will you convert ethanal into the following compound?
But-2-enal
Complete the synthesis by giving missing starting material, reagent or product.
\[\begin{array}{cc}
\ce{C6H5CHO}\phantom{............}\\
\phantom{........}\ce{+\phantom{......}\ce{->[dil.NaOH][\Delta]}}\phantom{...}\\
\ce{CH3CH2CHO}\phantom{............}
\end{array}\]
Give reasons Acetylation of aniline reduces its activation effect.
Write a chemical equation for the following reaction:
Propanone is treated with dilute Ba( OH)2.
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?
Why are carboxylic acids more acidic than alcohols or phenols although all of them have hydrogen atom attached to a oxygen atom \[\ce{(-O-H)}\]?
Assertion: Aromatic aldehydes and formaldehyde undergo Cannizaro reaction.
Reason: Aromatic aldehydes are almost as reactive as formaldehyde.
Identify A and B from the following reaction:
\[\begin{array}{cc}
\ce{CH3}\phantom{.................}\\
|\phantom{....................}\\
\phantom{}\ce{2CH3 - C = O ->[Ba(OH)2] A ->[Δ] B + H2O}
\end{array}\]
Predict the reagent for carrying out the following transformations:
Ethanal to 3-hydroxy butanal
Why is the α-hydrogens of aldehydes and ketones are acidic in nature?
