JEE Advanced levelSingle correct optionDifficulty 3 of 3g1190
Consider the carbocations I bis(4-methoxyphenyl)methyl cation, II diphenylmethyl cation and III bis(4-nitrophenyl)methyl cation. The correct order of stability is:
AII > I > III
BI > III > II
CIII > II > I
DI > II > III
Answer: D
In a diarylmethyl cation the charge is delocalised into both rings. A para methoxy group donates by +M and stabilises the cation, while a para nitro group withdraws electrons by -M and -I and destabilises it. So I > II > III.