Concept explainers
An unknown compound has the molecular formula C 9 H 11 B r. Its proton NMR spectrum shows the following absorptions:
singlet, δ 7.1, integral 44 mm
singlet, δ 2.3, integral 130 mm
singlet, δ 2.2, integral 67 mm
Propose a structure for this compound.
Interpretation:
The structure of the given unknown compound showing the given absorptions in the NMR spectrum is to be proposed.
Concept introduction:
NMR spectroscopy is a technique used to determine the unique structure of the compounds. It identifies the carbon-hydrogen bonding of an organic compound. A hydrogen atom is called as a proton in the NMR spectroscopy.
Answer to Problem 13.33SP
The structure of the given unknown compound showing the given absorptions in the NMR spectrum is given below.
Explanation of Solution
The molecular formula of the compound (
The double bond equivalent is calculated by the formula,
Substitute the given values in the above expression.
The DBE value is more than three and one signal present at
The other signals present in the NMR spectrum shows that,
From the above data analysis of
Figure 1
The structure of the given unknown compound showing the given absorptions in the NMR spectrum has been rightfully stated.
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Chapter 13 Solutions
Organic Chemistry (9th Edition)
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