Organic Chemistry

522 CHAPTER 13 Mass Spectrometry and Infrared Spectroscopy

47. Predict the major characteristic IR absorption bands that would be given by each of the following compounds:

a. d.

b. e.

c. f.

48. Given that the force constants are similar for and bonds, explain why the stretching vibration of a bond
    occurs at a greater wavenumber.


49. The IR spectrum of a compound with molecular formula was obtained in and is shown in Figure 13.42. Identify the
    compound.


50. The IR spectrum shown in Figure 13.43 is the spectrum of one of the following compounds. Identify the compound.

CH 2 OH COOH OH NH 2 CH 2 NH 2

C 5 H 8 O CCl 4

C¬H C¬C C¬H

CH 2 COH

O

O

CH 3 CH 2 CCH 2 CH 2 NH 2

CH 2 CCH

O

COCH 2 CH 3

O CH 2 CH 2 OH

CH 2 CHCH 2 CH

2.52.6 2.7 2.8 2.9 3 3.5 4 4.5 5 5.5 6 7 8 9 10 11 12 13 14 15 16

4000380036003400320030002800260024002200 2000 1800 1600 1400 1200 1000 800 600

Wavelength (μm)

Wavenumber (cm−^1 )

% Transmittance

% Transmittance

Wavelength (μm)

Wavenumber (cm−^1 )

2.52.6 2.7 2.8 2.9 3 3.5 4 4.5 5 5.5 6 7 8 9 10 11 12 13 14 15 16

4000380036003400320030002800260024002200 2000 1800 1600 1400 1200 1000 800 600

b.

c.

Figure 13.41 (continued)