CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317419
Give the stability order the following:
1 S \(>\) R \(>\) Q \(>\) P
2 P \(>\) Q \(>\) R \(>\) S
3 Q \(>\) P \(>\) R \(>\) S
4 \(\mathrm{P}>\mathrm{Q}>\mathrm{S}>\mathrm{R}\)
Explanation:
Benzyl Carbanion stability \({\rm{\alpha }} - {\rm{M}}, - {\rm{I}}\) groups at \(\mathrm{O} / \mathrm{P}\) positions. \(-\mathrm{NO}_{2}-\mathrm{CN}\) are \( - {\rm{M}}\) groups and \(-\mathrm{CH}_{3}\) is \({\rm{ + I}}\) group.
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317420
The three carbanions follow which order of stability?
1 I \(>\) II \(>\) III
2 I \(>\) III \(>\) II
3 II \(>\) I \(>\) III
4 II \(>\) III \(>\) I
Explanation:
In o-nitrobenzyl carbanion; and p-nitrobenzyl carbanion, \(-\mathrm{NO}_{2}\) group shows both \( - {\text{I}}\) and -R effect but \( - {\text{I}}\) effect is stronger in o-nitrobenzyl carbanion hence, it is more stable.In m-nitrobenzyl carbanion there is only \( - {\text{I}}\)-effect. Therefore, the stability order is
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317421
Correct order of stability of carbanion is
1 (I) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (IV)
2 (IV) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (I)
3 (IV) \({\mathrm{>}}\) (I) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (II)
4 (III) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (IV) \({\mathrm{>}}\) (I)
Explanation:
(IV) is aromatic as it contains \({\mathrm{6 \pi \mathrm{e}}}\) 's and follows Huckel's rule. So it is most stable. (I) is anti-aromatic. So it is least stable. (III) is more stable than (II) due to greater ring size. So, the correct option is (2).
JEE Main - 2024
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317422
The pair of electron in the given carbanion, \(\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{C}^{\Theta}\), is present in which of the following orbitals?
1 \({\rm{sp}}\)
2 \({\rm{2p}}\)
3 \({\rm{s}}{{\rm{p}}^{\rm{3}}}\)
4 \({\rm{s}}{{\rm{p}}^{\rm{2}}}\)
Explanation:
( \(2 \sigma+2 \pi\), -ve charge is considered to be sigma)
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317419
Give the stability order the following:
1 S \(>\) R \(>\) Q \(>\) P
2 P \(>\) Q \(>\) R \(>\) S
3 Q \(>\) P \(>\) R \(>\) S
4 \(\mathrm{P}>\mathrm{Q}>\mathrm{S}>\mathrm{R}\)
Explanation:
Benzyl Carbanion stability \({\rm{\alpha }} - {\rm{M}}, - {\rm{I}}\) groups at \(\mathrm{O} / \mathrm{P}\) positions. \(-\mathrm{NO}_{2}-\mathrm{CN}\) are \( - {\rm{M}}\) groups and \(-\mathrm{CH}_{3}\) is \({\rm{ + I}}\) group.
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317420
The three carbanions follow which order of stability?
1 I \(>\) II \(>\) III
2 I \(>\) III \(>\) II
3 II \(>\) I \(>\) III
4 II \(>\) III \(>\) I
Explanation:
In o-nitrobenzyl carbanion; and p-nitrobenzyl carbanion, \(-\mathrm{NO}_{2}\) group shows both \( - {\text{I}}\) and -R effect but \( - {\text{I}}\) effect is stronger in o-nitrobenzyl carbanion hence, it is more stable.In m-nitrobenzyl carbanion there is only \( - {\text{I}}\)-effect. Therefore, the stability order is
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317421
Correct order of stability of carbanion is
1 (I) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (IV)
2 (IV) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (I)
3 (IV) \({\mathrm{>}}\) (I) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (II)
4 (III) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (IV) \({\mathrm{>}}\) (I)
Explanation:
(IV) is aromatic as it contains \({\mathrm{6 \pi \mathrm{e}}}\) 's and follows Huckel's rule. So it is most stable. (I) is anti-aromatic. So it is least stable. (III) is more stable than (II) due to greater ring size. So, the correct option is (2).
JEE Main - 2024
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317422
The pair of electron in the given carbanion, \(\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{C}^{\Theta}\), is present in which of the following orbitals?
1 \({\rm{sp}}\)
2 \({\rm{2p}}\)
3 \({\rm{s}}{{\rm{p}}^{\rm{3}}}\)
4 \({\rm{s}}{{\rm{p}}^{\rm{2}}}\)
Explanation:
( \(2 \sigma+2 \pi\), -ve charge is considered to be sigma)
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317419
Give the stability order the following:
1 S \(>\) R \(>\) Q \(>\) P
2 P \(>\) Q \(>\) R \(>\) S
3 Q \(>\) P \(>\) R \(>\) S
4 \(\mathrm{P}>\mathrm{Q}>\mathrm{S}>\mathrm{R}\)
Explanation:
Benzyl Carbanion stability \({\rm{\alpha }} - {\rm{M}}, - {\rm{I}}\) groups at \(\mathrm{O} / \mathrm{P}\) positions. \(-\mathrm{NO}_{2}-\mathrm{CN}\) are \( - {\rm{M}}\) groups and \(-\mathrm{CH}_{3}\) is \({\rm{ + I}}\) group.
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317420
The three carbanions follow which order of stability?
1 I \(>\) II \(>\) III
2 I \(>\) III \(>\) II
3 II \(>\) I \(>\) III
4 II \(>\) III \(>\) I
Explanation:
In o-nitrobenzyl carbanion; and p-nitrobenzyl carbanion, \(-\mathrm{NO}_{2}\) group shows both \( - {\text{I}}\) and -R effect but \( - {\text{I}}\) effect is stronger in o-nitrobenzyl carbanion hence, it is more stable.In m-nitrobenzyl carbanion there is only \( - {\text{I}}\)-effect. Therefore, the stability order is
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317421
Correct order of stability of carbanion is
1 (I) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (IV)
2 (IV) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (I)
3 (IV) \({\mathrm{>}}\) (I) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (II)
4 (III) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (IV) \({\mathrm{>}}\) (I)
Explanation:
(IV) is aromatic as it contains \({\mathrm{6 \pi \mathrm{e}}}\) 's and follows Huckel's rule. So it is most stable. (I) is anti-aromatic. So it is least stable. (III) is more stable than (II) due to greater ring size. So, the correct option is (2).
JEE Main - 2024
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317422
The pair of electron in the given carbanion, \(\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{C}^{\Theta}\), is present in which of the following orbitals?
1 \({\rm{sp}}\)
2 \({\rm{2p}}\)
3 \({\rm{s}}{{\rm{p}}^{\rm{3}}}\)
4 \({\rm{s}}{{\rm{p}}^{\rm{2}}}\)
Explanation:
( \(2 \sigma+2 \pi\), -ve charge is considered to be sigma)
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317419
Give the stability order the following:
1 S \(>\) R \(>\) Q \(>\) P
2 P \(>\) Q \(>\) R \(>\) S
3 Q \(>\) P \(>\) R \(>\) S
4 \(\mathrm{P}>\mathrm{Q}>\mathrm{S}>\mathrm{R}\)
Explanation:
Benzyl Carbanion stability \({\rm{\alpha }} - {\rm{M}}, - {\rm{I}}\) groups at \(\mathrm{O} / \mathrm{P}\) positions. \(-\mathrm{NO}_{2}-\mathrm{CN}\) are \( - {\rm{M}}\) groups and \(-\mathrm{CH}_{3}\) is \({\rm{ + I}}\) group.
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317420
The three carbanions follow which order of stability?
1 I \(>\) II \(>\) III
2 I \(>\) III \(>\) II
3 II \(>\) I \(>\) III
4 II \(>\) III \(>\) I
Explanation:
In o-nitrobenzyl carbanion; and p-nitrobenzyl carbanion, \(-\mathrm{NO}_{2}\) group shows both \( - {\text{I}}\) and -R effect but \( - {\text{I}}\) effect is stronger in o-nitrobenzyl carbanion hence, it is more stable.In m-nitrobenzyl carbanion there is only \( - {\text{I}}\)-effect. Therefore, the stability order is
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317421
Correct order of stability of carbanion is
1 (I) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (IV)
2 (IV) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (I)
3 (IV) \({\mathrm{>}}\) (I) \({\mathrm{>}}\) (III) \({\mathrm{>}}\) (II)
4 (III) \({\mathrm{>}}\) (II) \({\mathrm{>}}\) (IV) \({\mathrm{>}}\) (I)
Explanation:
(IV) is aromatic as it contains \({\mathrm{6 \pi \mathrm{e}}}\) 's and follows Huckel's rule. So it is most stable. (I) is anti-aromatic. So it is least stable. (III) is more stable than (II) due to greater ring size. So, the correct option is (2).
JEE Main - 2024
CHXI12:ORGANIC CHEMISTRY SOME BASIC PRINCIPLES AND TECHNIQUES
317422
The pair of electron in the given carbanion, \(\mathrm{CH}_{3} \mathrm{C} \equiv \mathrm{C}^{\Theta}\), is present in which of the following orbitals?
1 \({\rm{sp}}\)
2 \({\rm{2p}}\)
3 \({\rm{s}}{{\rm{p}}^{\rm{3}}}\)
4 \({\rm{s}}{{\rm{p}}^{\rm{2}}}\)
Explanation:
( \(2 \sigma+2 \pi\), -ve charge is considered to be sigma)
