NMR Mosaic Faculty Page
The NMR Mosaic can help your students understand and visualize 1H NMR spectral interpretation.KEY FEATURES:
Additional information is available about how the NMR Mosaic works.
"I really like the NMR Mosaic. It not only makes the missing link in putting the pieces together, but also reinforces the need to use all information, shift, integration and splitting, in NMR analysis. Very nice!" Dr. Nancy Mills, Professor of Chemistry, Trinity University, San Antonio, Texas.
"I don't think I could have done the NMR problems without the NMR Mosaic. The pieces really helped me understand and visualize how the [spectral] peaks are related to the [molecular] fragments and how those fragments are put together to form the molecule." Holly Davis, Organic Student, Texas Lutheran University.
How Does it Work?
Your students will analyze each peak in the spectrum. Based on the integration, multiplicity, and chemical shift, they will construct molecular fragments (by affixing static cling pieces to base methyl, methylene, and methine pieces that make up the molecule). Read the quick instructions.
A PowerPoint presentation is available for download to explain NMR interpretation and show students how to interpret NMR spectra using the NMR Mosaic.
Dr. McClusky's presentation from the Southwest Regional ASC Meeting is available here.
Example problems for student practice are available here.
The fragments are then matched together to form the structure.
• More about how it works
The NMR Mosaic can help students catch interpretation errors
Note the peak at 2.5 δ would normally be interpreted
as a quartet, and the chemical shift would suggest a neighboring
carbonyl. This would cause construction of the following
fragment instead of the one shown.
However, in this case the molecule cannot be completed: not all the pieces match.
The piece that doesn't match indicates which peak was misinterpreted. The quartet must really be a doublet of triplets. After correcting the piece, the molecule is complete.The NMR Mosaic can help you interpret spectra with complex multiplets
Complex multiplets are very difficult to interpret because it can be impossible to determine how many next-door hydrogens there are. With the NMR Mosaic you don’t have to worry about it! The neighbor pieces will show you the correct piece.
Here is an example spectrum and the Mosaic pieces you should put together for each peak. For the complex multiplet CH2, don’t add any static cling pieces yet.
Now put these pieces together as best you can.
From the neighbors it is obvious that the multiplet CH2 is connected to a CH3 and CH, forming 2-chlorobutane.