Which of the following functional groups will exhibit no IR absorption at 1630 - 1780 cm^-1 or at 3200 - 3550 cm^-1?

Question

Quizplus · Accepted Answer

Ether functional group does not have any stretching or bending vibrations that occur in the 1630 - 1780 cm-1 region or in the 3200 - 3550 cm-1 region, so it will exhibit no IR absorption in these regions. The other functional groups have characteristic IR absorption bands in at least one of these regions.

Alcohols exhibit an absorption band in the region 3200-3600 cm-1 due to O-H stretching. Ketones exhibit a sharp absorption band at around 1715 cm-1 due to C=O stretching. Amides show strong absorption bands around 1650-1680 cm-1 due to C=O stretching and around 3200-3500 cm-1 due to N-H stretching vibrations. Aldehydes exhibit medium absorption bands at around 1720-1740 cm-1 due to C=O stretching.

Which of the Following Functional Groups Will Exhibit No IR