Concept explainers
Each of the following compounds is characterized by a 1H NMR spectrum that consists of
only a single peak having the chemical shift indicated. Identify each compound.
Interpretation:
The compounds gives only single peak in 1H NMR spectrum as indicated by the chemical shift is to be identified.
Concept introduction:
The information related to the proton in the compound can be deduced by the number of signals in a spectrum.
The proton chemical shift in the compound is due to the environment of the proton.
The signal of a particular proton can be split by the presence of protons in vicinal position.
The NMR spectrum of a compound will consist of a single peak if all protons in the compound are structurally equivalent.
Index of hydrogen deficiency is calculated as
Here
Oxygen atoms do not affect the index of hydrogen deficiency.
Answer to Problem 31P
Solution:
Explanation of Solution
Chemical formula:
A single peak at
Therefore, the structure of the compound is:
Chemical formula:
A single peak at
Therefore, it must be a symmetric cycloalkane:
Chemical formula:
A single peak at
Chemical formula:
The chemical formula shows it is a saturated alkyl halide. A single peak means that all protons are equivalent. The presence of the bromine atoms accounts for the higher chemical shift of the protons. Therefore, the structure of the compound is:
Chemical formula:
A single peak shows all protons to be equivalent. The formula is of a saturated alkyl halide. The presence of two chlorine atoms on the same carbon as the protons will increase the shift to
Chemical formula:
A single peak means all protons must be equivalent. The chemical formula shows it to be a saturated alkyl halide. The higher shift of
Chemical formula:
A single peak shows all protons to be equivalent. The chemical formula shows it to be a saturated alkyl halide. The high chemical shift of
Chemical formula:
A single peak shows all protons are equivalent. The chemical formula shows an index of hydrogen deficiency of four. This, taken together with a chemical shift of
Chemical formula:
A single peak shows all protons are equivalent. The higher chemical shift of
Therefore, the structure of the compound is:
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Chapter 14 Solutions
Loose Leaf Student Solutions Manual Organic Chemistry
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