Chapter 16, Problem 16.25YT

Interpretation Introduction

Interpretation:

The IR band in Figure 16-33 that indicates an $\text{OH}$ group is to be identified. In addition, the locations where you would expect to see absorptions corresponding to $\text{C=C}$ and alkyne $\text{C-H}$ stretches are to be identified.

Concept introduction:

In general, the $\text{H-O}$ signal occurs between $\text{3200}$ and ${\text{3600 cm}}^{\text{-1}}$ and gives rise to a broad and strong signal. In general, the $\text{C=C}$ signal occurs between $\text{2100}$ and ${\text{2260 cm}}^{\text{-1}}$ and gives rise to narrow signals varying in intensity. In general, the alkyne $\text{C-H}$ signal occurs at ${\text{3300 cm}}^{\text{-1}}$ and gives rise to a strong signal that is relatively narrow. In this example, the $\text{H-O}$ signal is centered around ${\text{3400 cm}}^{\text{-1}}$ and no signals are present for $\text{C=C}$ or alkyne $\text{C-H}$ (although it is possible that an alkyne $\text{C-H}$ signal could be buried under a $\text{H-O}$ signal).