Question

The following NMR peaks were recorded on a spectrometer operating at

200 MHz. Convert each into O¹units.

(a) CH₃CI; 1454Hz

(b) CHCI₃; 610Hz

(c) CH₃OH; 693Hz

(d) CH₂CI₂; 1060Hz

Short answer

(a)The value of $\delta$ for CHCI₃ is 7.27.

(b) The value of $\mathrm{\delta }$ for CH₃CI is 3.05.

(c) The value of $\mathrm{\delta }$ for CH₃OHis 3.46.

(d) The value of $\mathrm{\delta }$for isCH₂CI₂ 5.30.

Step-by-step solution

NMR spectroscopy

Nuclear magnetic resonance (NMR) spectroscopy constitutes a spectroscopic technique used to identify the structure of a particular molecule.A particular molecule’s carbon-hydrogen framework can be mapped using this technique. Several techniques like NMR, Mass and IR are combined to obtain the structure of even complex molecules.

Converting the given frequency into σunits in option (a)

(a)The observed chemical shift is 1454Hz .

The operating frequency of the ₁H NMR is 200 MHz .

The value of δ can be found as:

Hence, the value of $\mathrm{\delta }$is 7.27.

Converting the given frequency into δunits in option (b)

(b) The observed chemical shift is 610Hz .

The operating frequency of the ¹H NMR is 200 MHz .

The value of can be found as:

Hence, the value of $\mathrm{\delta }$is 3.46.

Converting the given frequency into σ units in option (d)

(d) The observed chemical shift is 1060 Hz.

The operating frequency of the ¹H NMR is 200 MHz.

The value ofδ can be found as:

Hence, the value of$\mathrm{\delta }$ is 5.30.