Chapter 20, Problem 48P

Interpretation Introduction

Interpretation:

The structure is to be proposed for compound $\text{B}$, which is an isomer of compound $\text{A}\left(\text{Problem}\text{20}\text{.47}\right)$ containing the molecular formula ${\text{C}}_{10}{\text{H}}_{\text{15}}\text{N}$.

Concept Introduction:

Carbon nuclear magnetic resonance ${(}^{\text{13}}\text{C}\text{NMR)}$ is considered homologous to the nuclear magnetic resonance ${(}^{\text{1}}\text{H}\text{NMR)}$.

In $\text{NMR}$ spectroscopy, the proton nuclear magnetic resonance ${(}^{\text{1}}\text{H}\text{NMR)}$ is used to find out the structure of molecules with the help of ${}^{\text{1}}\text{H}$ atom within the molecules.

The splitting of the molecules is determined by $\text{(n}+1)$ peaks in an $\text{NMR}$ resonance, where $\text{n}$ is the number of hydrogens on the adjacent atom.

Nuclear Magnetic Resonance (NMR) is one of the most capable analytical techniques used for determining the functional groups and how the atoms are structured and arranged in a molecule.

Few elements, such as ${}^{13}{\text{C and }}^1\text{H}$, have nuclei behaving as magnets about an axis. These elements are placed in magnetic field irradiated with electromagnetic energy of specific frequency and the nuclei tend 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 nuclear magnetic resonance (NMR).

In $\text{NMR}$ spectroscopy, the proton nuclear magnetic resonance ${(}^{\text{1}}\text{H}\text{NMR)}$ is used to find out the structure of molecules with the help of ${}^{\text{1}}\text{H}$ atom within the molecules.

Induced magnetic field consists of electricity generated from movement in a magnetic field.

The position of a signal on x-axis in the $\text{NMR}$ spectrum depicts the chemical shift expressed in $\delta$ or $\text{ppm}$.

The number of signals in $\text{H}\text{ NMR}$ spectrum represents the number of different chemical environments for the protons.

The area covered by the signal is proportional to the number of equivalent protons causing the signal.

The hydrogen atoms on adjacent carbon atoms split the signal into two or more peaks. One, two or three hydrogen atoms split the signal into two, three or four peaks described as doublet, triplet or quartet respectively.

A decrease in the electron density around a proton deshields the signal downfield at a larger value of chemical shift.

An increase in electron density shields the signal upfield at a lower value of chemical shift.

${}^{13}\text{C}$ NMR is only used in the observation of isotopes of carbon atoms.

Infrared spectroscopy is a simple, instrumental technique, which helps to determine the presence of various functional groups.

It depends on the interactions of atoms or molecules with the electromagnetic radiation.

Infrared spectroscopy is most commonly used in the identification of the structure of the compound.

Infrared spectroscopy is the examination of the infrared light interacting with a molecule. The examination can be done in three ways, that is, by measuring absorption, emission, and reflection, and it can also measure the vibration of atoms.