Q57 · CSIR-NET Chemistry, June 2018
Paper: CSIR-NET June 2018 · Subject: Organic Chemistry · Chapter: Organic Spectroscopy · Topic: Combined Structure Elucidation · Marks: 2 · Difficulty: Hard
A compound shows following spectral data. ${ }^{\mathrm{1}} \mathrm{H ~ NMR}: \delta=\mathrm{7 . 9}(\mathrm{d}, \mathrm{J}=\mathrm{8 ~ Hz}, \mathrm{2H}), \mathrm{6 . 6}(\mathrm{d}, \mathrm{J}=\mathrm{8} \mathrm{Hz}, 2 \mathrm{H}), 4.3(\mathrm{q}, J=6 \mathrm{Hz}, 2 \mathrm{H}) .4 .0\left(\mathrm{s}, \mathrm{D}_{2} \mathrm{O}\right.$ exchangeable), $1.4(\mathrm{t}, J=6 \mathrm{Hz}, 3 \mathrm{H})$ Mass: $m / z 165,137,120,92$ The correct structure of the compound is:
(a)
(b)
(c)
(d)
Answer
Answer: A ✓ checked by 4AB · confidence high
Explanation
para-Disubstituted benzene (7.9/6.6 doublets), OCH₂CH₃ (4.3 q, 1.4 t), exchangeable NH₂ (4.0) and M⁺ 165 (C₉H₁₁NO₂) identify ethyl 4-aminobenzoate (benzocaine); m/z 137 and 120 are loss of C₂H₄ and OEt.
Study loop for Organic Spectroscopy