A compound,X,C₉H₁₀O,which reacts with I₂/NaOH to give a pale yellow precipitate,gives the following ¹H NMR spectrum. Singlet, $\delta$2.38 Singlet, $\delta$2.54 Multiplet, (centered) $\delta$7.50 Which is a possible structure for X?

Question

Quizplus · Accepted Answer

The ¹H NMR spectrum of X shows three signals: two singlets at 2.38 and 2.54 ppm, and a multiplet centered at 7.50 ppm. This suggests that X contains three types of protons: two that are chemically equivalent (giving rise to the singlets), and one that is not (giving rise to the multiplet). Looking at the possible structures, only III contains three types of protons: two methyl protons (giving rise to the singlets) and a methine proton (giving rise to the multiplet). Structures I and IV contain only one type of proton (all protons are equivalent), which cannot explain the observed NMR spectrum. Structures II and V contain two types of protons (a methyl group and a methine group), but the chemical shifts of these groups are not consistent with the observed signals in the NMR spectrum. Therefore, the best choice is C) III.

A Compound,X,C9H10O,which Reacts with I2/NaOH to Give a Pale Yellow δ\deltaδ

A Compound,X,C₉H₁₀O,which Reacts with I₂/NaOH to Give a Pale Yellow $\delta$