Chapter 16: Ethers, Epoxides and Sulfides

Spectroscopic Analysis of Ethers

• IR  - presence of C-O

Absorbance (cm-1)	Interpretation
1200 -1250 (strong, broad)	C-O stretch

• ¹H NMR -  H-C-O-C unit is the most easily recognised (similar to H-COH of alcohols)

Resonance (ppm)	Interpretation
3.3 - 4.0	H-C-O (deshielding due to O)

• ¹³C NMR
  C-OH typically 57 - 87 ppm (deshielding due to O)

•   UV-VIS

Simple ethers give usually no absorption above 220 nm.
 
• Mass Spectrometry

Loss of alkyl radicals due to cleavage of branches adjacent to C-O is common.

© Dr. Ian Hunt, Department of Chemistry