IR Spectra, Mass Spectra, & NMR

O-H

3100-3650

N-H

3100-3650, primary (RNH2) has 2 bands while secondary (R2NH) has 1 band

C=C

1620-1680

Aromatic

1500, 1600

C≡C

2100-2260

C≡N

2160-2260

C-H (sp3)

2900-3000 (just below 3000)

C-H (sp2)

3000-3100 (just above 3000)

C-H (sp)

3200-3300

C=O

1680-1850

O=C-H

Two peaks at 2710, 2810

O=C-OH

3100-3650 and 1700

O=C-NR

1600-1650

C=O-O

1735

nitrogen

In mass spectra, an odd number of these means an odd mass

bromine

In mass spectra, M+ and M+2 peaks are on the same level

chlorine

In mass spectra, M+2 peak is 1/3 size of M+ peak

sulfur

In mass spectra, unusually large M+2 peak (appears small on graph) compared to M+

iodine

In mass spectra, peak at 127, large gap between M+ and cation

C-H

0-3 ppm

alkene

4.5-6.5 ppm

aromatic

6.5-8.5 ppm

aldehyde

9-10 ppm

acids

greater than 10 ppm (11-12)