Preparation of Ru(dmso)4Cl2
Students will work in groups of two. This experiment will involve the synthesis of an air-stable compound, Ru(dmso)4Cl2. The difficulty in the preparation is the fact that the intermediate in the reaction is air sensitive. To prepare this compound, students will use modified Schlenk line techniques. Once prepared, the yellow product is to be characterized by IR, 1H NMR and visible spectroscopy. This experiment is modified from Evans, I. P., Spencer, A., Wilkinson, G., J. C. S., Dalton Trans., 1973, 204-209.
1) Find the MSDS for the compounds used to make Ru(dmso)4Cl2. The starting reagents are ruthenium trichloride (ruthenium(III) chloride), dimethyl sulfoxide and acetone.
2) Preparation of Ru(dmso)4Cl2
Set up the apparatus as shown. In the 50 mL two-neck flask, dissolve 0.2 g of RuCl3 in 5 mL of DMSO and place under N2 by passing N2 over the solution for 10 min. This is done by removing the stopper from the second neck. After 10 min., replace the stopper and bring the solution to reflux. When the solution reaches reflux, note the time and reflux for 5 min. After the 5 min., remove the stopper and continue to heat under N2 until the volume is half the original volume. Replace stopper, remove from heat and let cool 5 - 10 min. before adding 20 mL of acetone. A yellow precipitate should form at this point. Filter and wash with acetone (two 5 mL portions). Let dry before obtaining a yield.
4) Characterization of Ru(dmso)4Cl2
You are to run the 1H NMR, IR and visible spectrum of your product.
5) Cost analysis
You will start with a lab that has two hoods, working gas, water and air jets, and plenty of bench and drawer space. Everything else you must purchase.
Write up Each person in the group must submit a separate report. The report must follow the guidelines on the Lab Report page and should include an introduction explaining how each instrument works (in theory) and what information each instrument gives about the compound. The experimental section will describe the procedure used for the preparation of the Ru(dmso)4Cl2. Gram and mole amounts should be listed for each reagent. Yield should be given as a gram amount as well as a percent yield. Students should also include the manufacturer for the IR and UV/visible spectrophotometers and the NMR spectrometer. Include the NMR, IR and visible spectra. Discuss the peak assignments in the NMR and IR of your compound. Attach the MSDS for each compound and include the cost analysis.
You must also detail how the compound will be synthesized, including diagram(s) for the synthetic apparatus(i) needed for your experiment. The report must include a schematic of the reactions. The apparatus(i) and schematic must be drawn using computer software of your choice. The report must include a cost analysis of all materials needed to do the synthesis and characterization including NMR, IR and UV/ visible spectrophotometers.
This lab will be worth 60 points and is due by 5:00 pm Friday, April
20, 2018. No late reports will be accepted.