Which of the following is the most stable carbanion?

Question

Which of the following is the most stable carbanion? (A) CH3 overset ominusCH2 (B) ( CH 3)2 CH (C) ( CH 3)3 overline C  (D) C6H5 overset-CH2

Tardigrade Admin · Accepted Answer

Benzyl carbanion is stabilized by resonance. Solution

electron-releasing groups (+I groups) make the carbanion less stable. Thus, a primary carbanion is more stable than secondary carbanion, which in turn, is more stable than a tertiary, because of +I effect associated with alkyl groups. Decreasing order of stabilities of carbanion is Solution

Electron-attracting groups (-I groups) like -NO2,-Br will stabilize carbanion by partial removal of the negative charge on the carbon.

Q. Which of the following is the most stable carbanion?

$C H_{3} C ⊖ H_{2}$

$(C H_{3})_{2} C H$

$(C H_{3})_{3} \overline{C}$

$C_{6} H_{5} C - H_{2}$

Q. Which of the following is the most stable carbanion?

CH3​C⊖H2​

(CH3​)2​CH

(CH3​)3​C

C6​H5​C−H2​

$C H_{3} C ⊖ H_{2}$

$(C H_{3})_{2} C H$

$(C H_{3})_{3} \overline{C}$

$C_{6} H_{5} C - H_{2}$