Chapter 9, Problem 49P

Interpretation Introduction

Interpretation:

The total ${}^{\text{1}}\text{H}\text{NMR}$ signal of the given compound is to be determined and tree diagram using coupling constant is to be drawn for the given compound.

Concept introduction:

▸ Few elements such as ${}^{13}{\text{C and }}^1\text{H}$ have nuclei behaving as a magnets about an axis, are placed in magnetic field irradiated with electromagnetic energy of specific frequency, the nuclei tends to absorb energy via magnetic resonance. There is this graph that shows energy absorption frequencies and intensities of a sample kept in the magnetic field called as nuclear magnetic resonance (NMR).

▸ Chemical shift is the measurement on $\delta$ scale (in ppm) where the peaks occur when the nuclei absorbs energy through magnetic resonance.

▸ NMR resonance generally splits into $\text{N}+1$ peaks, where N is number of hydrogen on the adjacent atoms. If there is no hydrogen present on the adjacent atom then resonance will be singlet. If there is one hydrogen present, then resonance will split into two peaks or have doublet. Two hydrogen on adjacent atoms splits into three peaks, a triplet and so on.

▸ The coupling constant is a measure of the interaction between a pair of protons which is represented by symbol J.