Exam I Questions

On the first exam, I anticipated that there would be a question requiring us to label important peaks for a given IR sectrum and the groups that produced them, rather than trying to identify the compound that best matches the spectrum. I expected the compound depicted in the IR spectrum to included either an alkene or alkyne, a hydroxyl group, and an amine or nitrile. With the table that was given, it would have been easy to identify these groups. Some of which can be easily identified without the table. The hydroxyl group would be easiest to identify, with or without the table; it is identified by one strong absorption between 3600cm-1 and 3200cm-1. It's the first thing I look for when trying to identify groups on the spectrum. The alkene could have been identified by the major Csp3-H peak at around 2900cm-1 and a small, sharp peak at 1650cm-1. If the compound had included an alkyne, it could have been identified by the major Csp3-H peak as well, but the second peak, being small and sharp, would have been at around 2250cm-1. If the compound shown had included an amine, however, I'm not sure whether or not the peak for the amine could be visible. This is because the amine shows two weak peaks at 3300cm-1 and 3400cm-1, requiring some of the same levels as the hydroxyl group (3600-3200cm-1). If a nitrile were present, it would have peaked at about 2250cm-1. This may have conflicted with the second peak of the alkyne, had it been present as well.