Alexander Sabre

Ethanal (acetaldehyde)

The NMR of acetaldehyde (ethanal)external image ImagesHandler.png: Acetaldehyde is an organic compound. It is a flammable liquid with a fruity smell. Acetaldehyde occurs naturally in ripe fuit, coffee, fresh bread, and is produced by plants as part of their normal metabolsim. It is popularly known as the chemical that causes hangovers.


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URL: <http://www.chemspider.com/Chemical-Structure.172.html> then click spectra

Figure 1: HNMR of Ethanal
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Figure 1: Please notice the trend of the two peaks located at 2.0 PPM, and the other at 9.35 PPM. The peak at 9.35 PPM coresponds withe the inclusion of a aldehyde group found in the molecule. The PEAK at 2.0 PPM corresponds with an alkane.

Figure 2: Showing of the coupling constant of the NMR
(http://www.wpi.edu/Academics/Depts/Chemistry/Courses/General/nmracetaldehyde.gif)

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Figure 2: Please take note of the doublet that occurs at 2.0 PPM, this is due to the CH3 group interaction with the single hydrogen that is next to to it. Due to the N+1 systematic property, the CH3 group is 1 plus another hydrogen is 1 equals 2, a doublet. Also take note that the peak at 9.35 PPM is actually a quartet. This is due to the Carbon-hydrogen interaction on on the side close to the C=O. This group plus the 3 hydrogens on the CH3 side according to N+1 give the number 4, the reason for the quartet. Also Note the peak that is 0.5 PPM, this value is classical of the methyl of an alkane.





Please take note that the website chem spider only provided one of these graphs, but that the second source was sited as displayed. Thank You.