Propionic acid with Br2/P yields a dibromo product. Its structure would be
A
B
CH2(Br) $$-$$ CH2 $$-$$ COBr
C
D
CH2(Br) $$-$$ CH(Br) $$-$$ COOH
Explanation
This is Hell–Volhard–Zelinsky reaction.
In
this reaction, acids containing $$\alpha $$-H react with
Br2
/red P giving product in which the $$\alpha $$-hydrogens
are substituted by Br.
2
AIPMT 2009
MCQ (Single Correct Answer)
Trichloroacetaldehyde, CCl3CHO reacts with chlorobenzene in presence of sulphuric acid and produces
A
B
C
D
Explanation
3
AIPMT 2008
MCQ (Single Correct Answer)
Acetophenone when reacted with a base, C2H5ONa, yields a stable compound which has the structure
A
B
C
D
Explanation
This reaction is known as aldol condensation.
C2H5ONa $$ \Rightarrow $$ C2H5O- + Na+
4
AIPMT 2008
MCQ (Single Correct Answer)
The relative reactivities of acyl compounds towards nucleophilic substitution are in the order of
A
Acid anhydride > Amide > Ester > Acyl chloride
B
Acyl chloride > Ester > Acid anhydride > Amide
C
Acyl chloride > Acid anhydride > Ester > Amide
D
Ester > Acyl chloride > Amide > Acid anhydride.
Explanation
The more the basic character of the leaving
group, the lesser is the reactivity the basic
character follows the order
NH2– > OR– > RCOO– > Cl–
Hence, the relative reactivities of acyl
compounds towards nucleophilic substitution
follow the order
Acyl halides > Acid anhydride
> Ester > Amide.
Questions Asked from Aldehydes, Ketones and Carboxylic Acids
On those following papers in MCQ (Single Correct Answer)
Number in Brackets after Paper Indicates No. of Questions