While isolated carbanions are typically hybridized, in which of the following species does the carba — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

In the allyl and benzyl carbanions, the negative charge is adjacent to a $\pi$ system. To achieve resonance stabilization, the carbanionic carbon rehybridizes to $sp^2$, placing the lone pair in an unhybridized p-orbital parallel to the adjacent $\pi$ system. Methyl and isopropyl lack adjacent $\pi$ bonds.