Which carbanion is more stable allyl karbonn a1 or benzyl carbanion?
Answers
Great this is one question where you have two different answers. Let me explain both of them.
Most of us believe benzyl carbocation is more stable than tertiary because benzyl carbocation involves in resonance.
Some of the authors believe that Tertiary carbocation is more stable as it involves maximum +I effect and maximum hyperconjuation +H (9 alpha hydrogens). Maximum +I and +H is more dominant than +M effect. Thus tertiary carbocation is more stable than benzyl carbocation.
So i suggest you to go for the answer according to the options provided , if one of the option you find benzyl is more than tertiary you can go for it else if it is given benzyl is more stable than tertiary then you go for it.
If both the options are there then the best one will be tertiary carbocation is more stable than benzyl
benzyl carbanion is more stable than allyl carboanion