Spectroscopic Features of Amines

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IR Spectroscopy

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Identifying amines via IR is limited to observing whether one or two N-H stretches are ecident. Primary amines have two, like here (a symmetric and an antisymmetric combination mode). Tertiary amines have no hydrogens, so of course they will show no absorption in this range.

1H NMR Spectroscopy

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The NH protons (if this is a primary or secondary amine) are typically broad and do not couple to adjacent protons. They are in the 1.0-3.0 region more often than not, but exchange can place them anywhere. (Aromatic N-H protons are usually well downfield.)
There is a deshielded signal for any proton on the adjacent carbon; between 2-3 ppm and will couple normally to its neighbors. The electronegativity of the nitrogen is less than oxygen, so there is less deshielding than you see in alcohols or ethers.

Click on any signal to highlight the proton responsible for it.

13C NMR Spectroscopy

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Nitrogen-bearing carbons are slightly deshielded..

Mass Spectroscopy

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The parent ion at m/z = 73 has an odd mass, indicating an odd number of nitrogens (1). The major peak is loss of a propyl group (C3H7, 43 mass units) by a process called "α-cleavage": the nitrogen is the site of ionization, and this pulls an electron from the adjacent C-C bond to make the iminium cation (H2C=NH2+, m/z = 30).