Chapter 9, Problem 24P

Interpretation Introduction

Interpretation:

The structure for an alcohol with molecular formula ${\text{C}}_5{\text{H}}_{12}\text{O}$ having ${}^1\text{H\hspace{0.17em}NMR}$ spectrum is to be proposed and chemical shifts and splitting pattern are to be assigned.

Concept introduction:

Few elements such as ${}^{13}{\text{C\hspace{0.17em}and\hspace{0.17em}}}^1\text{H}$ have nuclei behaving as magnets about an axis, are placed in magnetic field irradiated with electromagnetic energy of specific frequency, the nuclei tend to absorb energy via magnetic resonance. There is a graph that shows energy absorption frequencies and intensities of a sample kept in the magnetic field called nuclear magnetic resonance (NMR).

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

NMR resonance generally splits into $\text{N}+1$ peaks, where N is the number of hydrogen atoms 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 doublets.

Two hydrogen on adjacent atoms splits into three peaks, a triplet and so on.