A very simple lab synthesis that allows the student to carry out a coordination reaction and then look at the NMR and IR spectra. I use this as a first lab to introduce them to using the NMR and IR. If students work through the spectroscopy tutorial they should be able to explain the IR and NMR spectra.
A student should be able to explain simple NMR splitting patterns.
A student will use spectroscopy to show they have synthesized a desired compound.
Students will work through a spectroscopy tutorial http://www.chem.ualberta.ca/~inorglab/spectut/TblofCont.html
Vial with stir vane, stir plate, IR, NMR
I developed the lab from the paper by Arnaiz and have tried to get my students to use the spectroscopy tutorial. By asking them to do some analysis of spectra in the lab I hope to encourage the students to actually work through the tutorial. I need to add more NMR questions to the lab to make sure they work in depth on the tutorial.
Using a stir vane in the conical vial works well instead of using a stirring rod.
Have not tried the lab website combination yet but have tried each separately with some success.
A class of 6 students were all able to complete the synthesis with good yield. Students had to stir longer than indicated in the paper 10 minutes instead of 1 minute. The NMR was not great as it had limited solubility in the dueterated chloroform we had available. I have ordered the CD2CL2 suggested in the paper, hopefully this will solve the problem. IR seemed to be fine.
Students were within 1-10 degrees of the reported melting point of 179C. Good yields, 50-80% of resonably pure yellow product were obtained. The IR spectrum of the compound should show two strong bands at 900 and 930 cm-1 corresponding to the stretching vibrations characteristic of the cis MoO2. Singlets at 2.12 and 2.14 ppm (CD2Cl2, room temperature) should be seen, assignable to the two sets of inequivalent methyl groups in the 1H NMR spectrum.