323633
Read the Statement - A and Statement - B carefully and mark the correct option. Statement A : under Clemmensen reduction conditions will give Statement B : under Wolff - Kishner reduction conditions will give
1 Statement A is true but Statement B is false.
2 Both Statement A and Statement B are true.
3 Statement A is false but Statement B is true.
4 Both Statement A and Statement B are false.
Explanation:
In clemmensen reduction conditions, acid derivatives are hydrolysed to acids and carbonyl group is reduced to \(-\mathrm{CH}_{2}-\) group.
In wolf-kishner reduction, carbonyl group is reduced to \(-\mathrm{CH}_{2}-\) group. Here -Cl is present, so undergoes dehydrogenation in presence of base.
JEE - 2023
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323634
Which of the following cannot be used to convert RCHO into \(\mathrm{RCH}_{2} \mathrm{OH}\) ?
1 \(\mathrm{H}_{2} / \mathrm{Pd}\)
2 \(\mathrm{LiAlH}_{4}\)
3 \(\mathrm{NaBH}_{4}\)
4 Reaction with \(\mathrm{RMgX}\) followed by hydrolysis
Explanation:
\(\mathrm{H}_{2} / \mathrm{Pd}, \mathrm{LiAlH}_{4}, \mathrm{NaBH}_{4}\) will convert \(\mathrm{R}\) - CHO into \(\mathrm{R}-\mathrm{CH}_{2} \mathrm{OH}\) by reduction. Aldehyde is converted into \(2^{\circ}\) alcohol with Grignard reagent.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323635
Which from the following reactions converts carbonyl group of aldehydes and ketones to methylene group on treatment with zinc amalgam and concentrated \(\mathrm{HCl}\) ?
1 Wolff - Kishner reduction
2 Stephen reduction
3 Clemmensen reduction
4 Rosenmund reduction
Explanation:
It is Clemmensen reduction.
MHTCET - 2021
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323636
Clemmensen reaction of ketone is carried out in the presence of
1 \(\mathrm{LiAlH}_{4}\)
2 \(\mathrm{Zn}-\mathrm{Hg}\) with \(\mathrm{HCl}\)
3 glycol with \(\mathrm{KOH}\)
4 \(\mathrm{H}_{2}\) with Pt as catalyst
Explanation:
\(\mathrm{Zn}-\mathrm{Hg}\) with \(\mathrm{HCl}\) reduces ketone to respective alkane, i.e.\(\mathrm{C}=\mathrm{O}\) of ketone reduce to \(>\mathrm{CH}_{2}\) group. The reaction is called Clemmensen reduction.
NEET Test Series from KOTA - 10 Papers In MS WORD
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CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323633
Read the Statement - A and Statement - B carefully and mark the correct option. Statement A : under Clemmensen reduction conditions will give Statement B : under Wolff - Kishner reduction conditions will give
1 Statement A is true but Statement B is false.
2 Both Statement A and Statement B are true.
3 Statement A is false but Statement B is true.
4 Both Statement A and Statement B are false.
Explanation:
In clemmensen reduction conditions, acid derivatives are hydrolysed to acids and carbonyl group is reduced to \(-\mathrm{CH}_{2}-\) group.
In wolf-kishner reduction, carbonyl group is reduced to \(-\mathrm{CH}_{2}-\) group. Here -Cl is present, so undergoes dehydrogenation in presence of base.
JEE - 2023
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323634
Which of the following cannot be used to convert RCHO into \(\mathrm{RCH}_{2} \mathrm{OH}\) ?
1 \(\mathrm{H}_{2} / \mathrm{Pd}\)
2 \(\mathrm{LiAlH}_{4}\)
3 \(\mathrm{NaBH}_{4}\)
4 Reaction with \(\mathrm{RMgX}\) followed by hydrolysis
Explanation:
\(\mathrm{H}_{2} / \mathrm{Pd}, \mathrm{LiAlH}_{4}, \mathrm{NaBH}_{4}\) will convert \(\mathrm{R}\) - CHO into \(\mathrm{R}-\mathrm{CH}_{2} \mathrm{OH}\) by reduction. Aldehyde is converted into \(2^{\circ}\) alcohol with Grignard reagent.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323635
Which from the following reactions converts carbonyl group of aldehydes and ketones to methylene group on treatment with zinc amalgam and concentrated \(\mathrm{HCl}\) ?
1 Wolff - Kishner reduction
2 Stephen reduction
3 Clemmensen reduction
4 Rosenmund reduction
Explanation:
It is Clemmensen reduction.
MHTCET - 2021
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323636
Clemmensen reaction of ketone is carried out in the presence of
1 \(\mathrm{LiAlH}_{4}\)
2 \(\mathrm{Zn}-\mathrm{Hg}\) with \(\mathrm{HCl}\)
3 glycol with \(\mathrm{KOH}\)
4 \(\mathrm{H}_{2}\) with Pt as catalyst
Explanation:
\(\mathrm{Zn}-\mathrm{Hg}\) with \(\mathrm{HCl}\) reduces ketone to respective alkane, i.e.\(\mathrm{C}=\mathrm{O}\) of ketone reduce to \(>\mathrm{CH}_{2}\) group. The reaction is called Clemmensen reduction.
323633
Read the Statement - A and Statement - B carefully and mark the correct option. Statement A : under Clemmensen reduction conditions will give Statement B : under Wolff - Kishner reduction conditions will give
1 Statement A is true but Statement B is false.
2 Both Statement A and Statement B are true.
3 Statement A is false but Statement B is true.
4 Both Statement A and Statement B are false.
Explanation:
In clemmensen reduction conditions, acid derivatives are hydrolysed to acids and carbonyl group is reduced to \(-\mathrm{CH}_{2}-\) group.
In wolf-kishner reduction, carbonyl group is reduced to \(-\mathrm{CH}_{2}-\) group. Here -Cl is present, so undergoes dehydrogenation in presence of base.
JEE - 2023
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323634
Which of the following cannot be used to convert RCHO into \(\mathrm{RCH}_{2} \mathrm{OH}\) ?
1 \(\mathrm{H}_{2} / \mathrm{Pd}\)
2 \(\mathrm{LiAlH}_{4}\)
3 \(\mathrm{NaBH}_{4}\)
4 Reaction with \(\mathrm{RMgX}\) followed by hydrolysis
Explanation:
\(\mathrm{H}_{2} / \mathrm{Pd}, \mathrm{LiAlH}_{4}, \mathrm{NaBH}_{4}\) will convert \(\mathrm{R}\) - CHO into \(\mathrm{R}-\mathrm{CH}_{2} \mathrm{OH}\) by reduction. Aldehyde is converted into \(2^{\circ}\) alcohol with Grignard reagent.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323635
Which from the following reactions converts carbonyl group of aldehydes and ketones to methylene group on treatment with zinc amalgam and concentrated \(\mathrm{HCl}\) ?
1 Wolff - Kishner reduction
2 Stephen reduction
3 Clemmensen reduction
4 Rosenmund reduction
Explanation:
It is Clemmensen reduction.
MHTCET - 2021
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323636
Clemmensen reaction of ketone is carried out in the presence of
1 \(\mathrm{LiAlH}_{4}\)
2 \(\mathrm{Zn}-\mathrm{Hg}\) with \(\mathrm{HCl}\)
3 glycol with \(\mathrm{KOH}\)
4 \(\mathrm{H}_{2}\) with Pt as catalyst
Explanation:
\(\mathrm{Zn}-\mathrm{Hg}\) with \(\mathrm{HCl}\) reduces ketone to respective alkane, i.e.\(\mathrm{C}=\mathrm{O}\) of ketone reduce to \(>\mathrm{CH}_{2}\) group. The reaction is called Clemmensen reduction.
323633
Read the Statement - A and Statement - B carefully and mark the correct option. Statement A : under Clemmensen reduction conditions will give Statement B : under Wolff - Kishner reduction conditions will give
1 Statement A is true but Statement B is false.
2 Both Statement A and Statement B are true.
3 Statement A is false but Statement B is true.
4 Both Statement A and Statement B are false.
Explanation:
In clemmensen reduction conditions, acid derivatives are hydrolysed to acids and carbonyl group is reduced to \(-\mathrm{CH}_{2}-\) group.
In wolf-kishner reduction, carbonyl group is reduced to \(-\mathrm{CH}_{2}-\) group. Here -Cl is present, so undergoes dehydrogenation in presence of base.
JEE - 2023
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323634
Which of the following cannot be used to convert RCHO into \(\mathrm{RCH}_{2} \mathrm{OH}\) ?
1 \(\mathrm{H}_{2} / \mathrm{Pd}\)
2 \(\mathrm{LiAlH}_{4}\)
3 \(\mathrm{NaBH}_{4}\)
4 Reaction with \(\mathrm{RMgX}\) followed by hydrolysis
Explanation:
\(\mathrm{H}_{2} / \mathrm{Pd}, \mathrm{LiAlH}_{4}, \mathrm{NaBH}_{4}\) will convert \(\mathrm{R}\) - CHO into \(\mathrm{R}-\mathrm{CH}_{2} \mathrm{OH}\) by reduction. Aldehyde is converted into \(2^{\circ}\) alcohol with Grignard reagent.
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323635
Which from the following reactions converts carbonyl group of aldehydes and ketones to methylene group on treatment with zinc amalgam and concentrated \(\mathrm{HCl}\) ?
1 Wolff - Kishner reduction
2 Stephen reduction
3 Clemmensen reduction
4 Rosenmund reduction
Explanation:
It is Clemmensen reduction.
MHTCET - 2021
CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323636
Clemmensen reaction of ketone is carried out in the presence of
1 \(\mathrm{LiAlH}_{4}\)
2 \(\mathrm{Zn}-\mathrm{Hg}\) with \(\mathrm{HCl}\)
3 glycol with \(\mathrm{KOH}\)
4 \(\mathrm{H}_{2}\) with Pt as catalyst
Explanation:
\(\mathrm{Zn}-\mathrm{Hg}\) with \(\mathrm{HCl}\) reduces ketone to respective alkane, i.e.\(\mathrm{C}=\mathrm{O}\) of ketone reduce to \(>\mathrm{CH}_{2}\) group. The reaction is called Clemmensen reduction.
