University:
California State University, Northridge
Course:
CHEM 321/L | Chemical Analysis I and Lab
Academic year:

2023
Views:

296

Pages:

2
Author:

Hermione S.

Selected Infrared Correlations Hydrocarbons Alkyl C–H stretch 3000–2840 cm-1 variable, multiple absorptions Aromatic C–H stretch 3080–3030 cm-1 Alkenyl C–H stretch 3095–3010 cm-1 variable, multiple absorptions medium, Alkynyl C–H stretch 3340–3250 cm-1 multiple absorptions strong Aromatic C–C stretch 1625–1575, 1610–1560, 1525–1450, and 1470–1440 cm-1 1690–1635 cm-1 1640–1620 cm-1 2260–2190 cm-1 2140–2100 cm-1 variable, four absorptions medium weak weak medium Alkyl Halides C–F stretch C–Cl stretch C–Br stretch C–I stretch 1400–1000 cm-1 830–600 cm-1 700–500 cm-1 650–450 cm-1 strong strong strong strong Alcohols O–H stretch 3650–3200 cm-1 strong, broad 1260–970 cm-1 strong Ethers C–O stretch 1310–1000 and 1055–870 cm-1 strong, two absorptions Amines N–H stretch (1o amine) 3500–3300 cm-1 N–H stretch (2o amine) 3450–3300 cm-1 medium, two absorptions medium Aromatic C–N stretch Aliphatic C–N stretch 1360–1250 cm-1 1400–1000 cm-1 medium weak–medium Isolated Alkenyl C=C stretch Conjugated Alkenyl C=C stretch Internal Alkynyl C≡C stretch Terminal Alkynyl C≡C stretch C–O stretch Imines C=N stretch 1690–1520 cm-1 usually strong Nitriles C≡N stretch 2260–2215 cm-1 medium–strong Carbonyl Compounds C=O stretch ketone aldehyde 1870–1630 cm-1 1775–1650 cm-1 1765–1645 cm-1 strong ester lactone carboxylic acid acid anhydride acid chloride amide lactam 1800–1650 cm-1 1840–1730 cm-1 1800–1650 cm-1 1870–1770 and 1830–1720 cm-1 1820–1720 cm-1 1740–1630 cm-1 1780–1650 cm-1 two absorptions C–H stretch (aldehyde) 2900–2800 and 2780–2680 cm-1 weak, two absorptions O–H stretch (carboxylic acid) 3550–2500 cm-1 very broad N–H stretch (1o amide) 3500–3350 and 3400–3100 cm-1 N–H stretch (2o amide) 3500–3100 cm-1 medium, two absorptions medium Notes: 1. The effect of conjugation is to decrease a functional group's absorption maximum to a lower wavenumber. The effect of angle strain is to increase a functional group's absorption maximum to a higher wavenumber. 2. See Appendices 2A and 2B of Wade, Organic Chemistry, for much more detailed infrared correlation tables.