1H-NMR spectroscopy, 13C-NMR spectroscopy, 19F-NMR spectroscopy, IR spectroscopy and GC-Mass spectrometry are used throughout CHEM 344 to analyze, interpret, and rationalize experimental results. It is critical that you develop a working knowledge of how each of these techniques provides structural information about organic molecules. As is often the case in organic chemistry research, 1H-NMR spectroscopy will be used more than the other techniques and is an important point of emphasis in this course.
In order to ensure that each student’s problem-solving skills are adequate to interpret the spectra produced in the course, the laboratory sessions are devoted to interpreting these spectra. The general schedule is detailed below as well as many useful links. For each of the first four laboratory days, there are pre-recorded video lectures that must be watched prior to attending the laboratory session. The laboratory section will begin with TA-led activities designed to reinforce and further develop the lecture video material. For each day additional links and textbook readings are provided. Viewing of the video lectures is required before attending the corresponding laboratory session. Notetaking slides are available for the entire presentation; its usage is highly encouraged.
Loudon Chapter 12, 14.3, 15.2, 16.3A, 16.3D, 19.3A, 19.3D, 19.3E, 20.3A, 21.4A, 23.4A, & A-2
Loudon Chapter 13, 14.3C, 16.3B, 16.3C, 19.3B, 19.3C, 20.3B, 21.4B, & 23.4B
Estimating the 1H shifts of aryl H-nuclei This is a handout that explains how to assign the H-nuclei of an aromatic molecule to its 1H-NMR spectrum using a variety of methods.
Calculating Product Ratios from 1H-NMR Spectroscopy This is a useful handout that explains how to use the 1H-NMR spectrum of a mixture of compounds to determine the relative abundance of each component.
Determining Stereochemistry of a substituted 5-membered ring by 1H-NMR Spectroscopy This is a course handout that details how to use 1H-NMR spectroscopy to determine the stereochemistry of an dimethylsubstituted 5-membered ring.
Spectral Database for Organic Compounds (SDBS) This website is an excellent (free) database of experimental EI-MS, 13C-NMR, 1H-NMR, IR, Raman, and ESR spectra. These are great to use as model compounds for similar molecules or to confirm your spectroscopic assignments.
NMR Chemical Shifts of Trace Impurities: Common Laboratory Solvents, Organics, and Gases in Deuterated Solvents Relevant to the Organometallic Chemist This article contains the NMR chemical shifts of a lot of common solvents that may be present in your laboratory NMR spectra.
Students are required to download and analyze their own 1H-NMR, 19F-NMR, GC-MS and IR data. The NMR data are usually obtained by an instructor in <48 hours and will be available via the course website, but will require workup by the student (see below). Likewise, the GC-MS data are made available on the course website usually in <48 hours (see details). The IR spectra are obtained in class and available immediately.
NMR Data Workup Instructions
The raw free-induction decay (FID) NMR data will be available on the course website and will need to be worked up in a program such as MestReNova (available for Windows, Mac OSX, Linux). This requires that you have followed the MestReNova License and Installation Notes.
The first time you open the software and install the .lic license file, you must be connected directly (by network cable and not wireless) to the chemistry building network or via GlobalProtect to WiscVPN (wiscvpn.doit.wisc.edu) from anywhere in the world. You must connect to the Chemistry network or WiscVPN every 90 days for the license to be valid. Videos showing the installation process for PC and Mac are shown below.
WiscVPN – Downloading and Installing the GlobalProtect (PaloAlto) Client PC or Mac (necessary for activating MestReNova license off campus or on campus via wireless)
See the lab manual appendicies for assistance.
- Open the FID file in MestReNova.
You must extract the folder containing the fid file from the larger zip file. You may open the fid from within MestReNova or simply drag the fid containing folder onto the MestReNova icon. For historical reasons, the fid does not have a file extension and will not be recognized as any particular file type by a mac or pc.
- Workup the spectrum as desired/instructed.
Each experiment will have unique needs for how the spectrum should be worked up. There will be a set of directions for each experiment and a sample spectrum for you to compare to. For the first few experiments, there will be a video demonstration of how to use MestReNova to produce the desired spectrum. See the individual experiment for further details.