15. Analytical Techniques:IR, NMR, Mass Spect

For the hydrogen(s) screened in blue, draw the signal you would expect to see in a ¹H NMR spectrum. At which chemical shift would the signal appear?

(c)

Though it wasn't discussed, what coupling constant would you expect for Hₐ and H꜀ in the spectrum of trans-but-2-enoic acid in Figure 15.50? Justify your answer.

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Sketch the signals you would expect to see for H_b in the molecule shown. The important coupling constants are given.

A chemist made what was thought to be compound A or B. How could coupling constants between H_a and H_b be used to distinguish between the two isomers? [Hint: Draw a chair conformation of each.]

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

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

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Sketch the signals you would expect to see for H꜀ in the molecule shown. The important coupling constants are given.

Draw the expected signal for a hydrogen with the following coupling constants.

(b) Hₐ : δ 3.34 (Jₐ꜀ = 9 , Jₐ₆ = 4 )

Sketch the signals you would expect to see for Hₐ in the molecule shown. The important coupling constants are given.

For the hydrogen(s) screened in blue, draw the signal you would expect to see in a ¹H NMR spectrum. At which chemical shift would the signal appear?

(e)

Predict the splitting pattern for each of the indicated hydrogens in Assessment 15.59.

(d)