What strength magnetic field is required when a 500-MHz instrument is used for ¹H NMR?

How many signals would you expect to see in the ¹H NMR spectrum of each of the five compounds with molecular formula C₆H₁₄?

How many signals would you expect to see in the 1H NMR spectrum of each of the following compounds?

a. CH₃CH₂CH₂CH₃

b. BrCH₂CH₂Br

How many signals would you expect to see in the 1H NMR spectrum of each of the following compounds?

e.

f.

How many signals would you expect to see in the 1H NMR spectrum of each of the following compounds?

g.

h.

How many signals would you expect to see in the 1H NMR spectrum of each of the following compounds?

m.

n.

o.

Draw an isomer of dichlorocyclopropane that gives an ¹H NMR spectrum

c. with three signals

If two signals differ by 1.5 ppm in a 300 MHz spectrometer, by how much do they differ in a 500 MHz spectrometer?

If two signals differ by 90 Hz in a 300 MHz spectrometer, by how much do they differ in a 500 MHz spectrometer

Which underlined proton (or sets of protons) has the greater chemical shift (that is, the higher frequency signal)?

c.

d.

Which underlined proton (or sets of protons) has the greater chemical shift (that is, the higher frequency signal)?

a.

b.

Without referring to Table 14.1, label the proton or set of protons in each compound that gives the signal at the lowest frequency a, at the next lowest b, and so on.

c. ClCH₂CH₂CH₂Cl

Without referring to Table 14.1, label the proton or set of protons in each compound that gives the signal at the lowest frequency a, at the next lowest b, and so on.

e.

Without referring to Table 14.1, label the proton or set of protons in each compound that gives the signal at the lowest frequency a, at the next lowest b, and so on.

h.

[18]-Annulene shows two signals in its ¹H NMR spectrum: one at 9.25 ppm and the other to the right of the TMS signal at –2.88 ppm. What hydrogens are responsible for each of the signals? (Hint: Look at the direction of the induced magnetic field outside and inside the benzene ring in Figure 14.6.)

How would integration distinguish the ¹H NMR spectra of the following compounds?

Which of the following compounds is responsible for the ¹H NMR spectrum shown below?

<IMAGE>

Explain how the following compounds, each with the same molecular formula, could be distinguished by their ¹H NMR spectra.

Draw a diagram like the one shown in Figure 14.12 to predict

a. the relative intensities of the peaks in a triplet.

<IMAGE>

Draw a diagram like the one shown in Figure 14.12 to predict

b. the relative intensities of the peaks in a quintet.

<IMAGE>

Indicate the number of signals and the multiplicity of each signal in the 1H NMR spectrum of each of the following compounds:

a. CH₃CH₂CH₂CH₂CH₂CH₃

Indicate the number of signals and the multiplicity of each signal in the 1H NMR spectrum of each of the following compounds:

c. ClCH₂CH₂CH₂Cl 

Explain the relative chemical shifts of the benzene ring protons in Figure 14.18.

<IMAGE>

Identify each compound from its molecular formula and its ¹H NMR spectrum:

b. C₅H₁₀O

<IMAGE>

Predict the splitting patterns for the signals given by the compounds in Problem 4.

c. CH₂=CCl₂

Predict the splitting patterns for the signals given by the compounds in Problem 4.

d.

Predict the splitting patterns for the signals given by the compounds in Problem 4.

i.

Predict the splitting patterns for the signals given by the compounds in Problem 4.

j.

Describe the ¹H NMR spectrum you would expect for each of the following compounds, indicating the relative positions of the signals:

b. CH₃OCH₂CH₂CH₂Br

Describe the ¹H NMR spectrum you would expect for each of the following compounds, indicating the relative positions of the signals:

d.