Sketch your predictions of the proton NMR spectra of the following compounds.
(b)

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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Tell precisely how you would use the proton NMR spectra to distinguish between the following pairs of compounds.

(a) 1-bromopropane and 2-bromopropane

The following proton NMR spectrum is of a compound of molecular formula C₃H₈O.

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(a) Propose a structure for this compound.

(b) Assign peaks to show which protons give rise to which signals in the spectrum.

Tell precisely how you would use the proton NMR spectra to distinguish between the following pairs of compounds.

(b)

Sketch your predictions of the proton NMR spectra of the following compounds.

(a) CH₃–O–CH₂CH₃

Using a 60-MHz spectrometer, a chemist observes the following absorption: doublet, J = 7 Hz, at δ4.00

(a) What would the chemical shift (δ) be in the 300-MHz spectrum?

(b) What would the splitting value J be in the 300-MHz spectrum?

(c) How many hertz from the TMS peak is this absorption in the 60-MHz spectrum? In the 300-MHz spectrum?