The natural product that gives a signal at 218 ppm in its ¹³ C NMR spectrum is

Q101 · CSIR-NET Chemistry, December 2019

Paper: CSIR-NET December 2019 · Subject: Organic Chemistry · Chapter: Organic Spectroscopy · Topic: NMR 1H · Marks: 2 · Difficulty: Easy

The natural product that gives a signal at 218 ppm in its ${ }^{13} \mathrm{C} \mathrm{NMR}$ spectrum is

(a)$\alpha$-pinene

(b)camphor

(c)geraniol

(d)carvones

Answer

Answer: B ✓ checked by 4AB · confidence high

The source book printed D; on checking, B is correct — see the explanation.

Printed D; carvone's carbonyl is conjugated and appears near 199 ppm.

Explanation

δ 218 is a saturated ketone carbonyl — camphor; carvone's conjugated enone is near 199, and the others have no C=O.

Study loop for Organic Spectroscopy