Chemistry - GOC Question with Solution | TestHub

(A) S$bC{l}_5$ removes $C{l}^{-}$ and gives the aromatic cyclopropenyl cation. (B) 2 BuLi removes both chlorines to give the pentalene dianion (10π, aromatic). (C) loss of HCl leads to the aromatic tropone system. (D) $S_N$₁ would need the cyclopentadienyl cation (4π, anti-aromatic), which is very unstable, so the reaction does not proceed.