Concept explainers
The
two signals, one due to the
absorption. (b) Do the
(a)
Interpretation: The chemical shifts of the given absorptions are to be calculated.
Concept introduction: In NMR spectrum, peaks are known as resonances, lines or absorptions. On the horizontal axis, the position of absorption is generally referred to as chemical shift. The chemical shift of any absorption is calculated by the formula,
Answer to Problem 14.1P
The chemical shifts of the given absorptions are
Explanation of Solution
The observed chemical shift due to the
The observed chemical shift due to the
The operating frequency is
The conversion of
Therefore, the conversion of
Chemical shift
Chemical shift due to
The chemical shift of absorption is calculated by the formula,
Where,
Substitute the values of observed chemical shift and operating frequency in the above formula to calculate the chemical shift due to
Therefore, the chemical shift is
The conversion of
Therefore, the conversion of
Hence, the chemical shift is
Chemical shift due to
Substitute the values of observed chemical shift and operating frequency in the above formula to calculate the chemical shift due to
Therefore, the chemical shift is
The conversion of
Therefore, the conversion of
Hence, the chemical shift is
The chemical shifts of the given absorptions are
(b)
Interpretation: Whether the
Concept introduction: In NMR spectrum, peaks are known as resonances, lines or absorptions. On the horizontal axis, the position of absorption is generally referred to as chemical shift. The increasing order of chemical shift is plotted from right to left in NMR spectrum.
Answer to Problem 14.1P
The peak of
Explanation of Solution
The terms, upfield and downfield expresses the relative location of signals. The meaning of upfield is to the right and of downfield is to the left. The
Figure 1
Hence, the peak of
The peak of
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Chapter 14 Solutions
Organic Chemistry
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