BackGiven the ¹H NMR spectrum and the molecular formula, suggest a structure for each molecule. [The IR spectrum suggests the presence of two C=O bonds.]
(a) Important IR bands (cm ⁻ ¹) : 1728, 1708 [Note: The pKₐ of this molecule is around 10.]
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A small pilot plant was adding bromine across the double bond of but-2-ene to make 2,3-dibromobutane. A controller malfunction allowed the reaction temperature to rise beyond safe limits. A careful distillation of the product showed that several impurities had formed, including the one having the NMR spectra that appear below. Determine its structure, and assign the peaks to the protons in your structure.
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Identify pairs of coupled protons in the compound whose COSY spectrum is shown below.
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What does cross peak X in Figure 14.34 tell you?
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The 1H NMR spectrum of 2-propen-1-ol is shown here. Indicate the protons in the molecule that are responsible for each of the signals in the spectrum.
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