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Colleagues,
I hope all is well. I am thinking about bring some rhenium chemistry into the inorganic lab. I could have the students prepare [ReO2(py)4]Cl and characterize it using IR,NMR, UV-vis. What are your thoughts on this idea? This complex is really easy to make starting with [ReOCl3(PPh3)2] and excess pyridine. You let it reflux in acetone/H2O for 90 minutes. I thought about this because [ReO2(py)4]Cl is actually a starting material for my research efforts.
Sibrina
It's ALWAYS a good idea to have your lab students make starting materials for research! I think the IR of the oxo would be great; is it easily visible? I bet the comparison of the IR between starting material and product would be a good review of symmetry and IR bands. Sounds like a great plan!
Adam
Rhenium chemistry is fun (I'm biased because our lab does Rhenium electrochemistry)!
You could also do the lower oxidation state stuff: substitution reactions of Re(CO)5Cl to make Re(L)2(CO)3Cl (L = monodentate amines, pyridines, or phosphines or bidentate groups) and have GREAT IR handles, or use Re2(CO)10 to make binuclear complexes. You could correspond the IR stretches to the geometry and have them discuss ligand electron-donating abilities and back-bonding. The literature is quite large regarding these complexes.
You can also do the corresponding Manganese work starting from commercially available Mn(CO)5Br or Mn2(CO)10
Its all diamagnetic, so you can get good NMRs too if you use phosphines or ligands with a lot of Hydrogens.
The starting materials and products are generally pretty air-stable.
Adam and Kyle,
These are really neat suggestions. One thing that I find most interesting about the [ReO2(py)4]Cl.2H2O complex is that usually the only IR peak that is reported in the literature is a peak at 820 cm-1 for the O=Re=O stretch. There are so many other peaks in the spectra. I had not thought about the corresponding Mn complexes. That is a neat idea.
Sibrina
Adam and Kyle, I have been doing a little reading on applications of rhenium complexes, specifically for the applications of OLEDs. Most of the research on heavy metals to fabricate OLED devices focuses on platinum(II) and iridum(III) complexes. However, rhenium(I) complexes are getting some attention now as well. Could oxorhenium(V) complexes be used to fabricate OLED devices? To have emission from an OLED based on metal complex, you need two things, namely a triplet MLCT state and strong spin orbit coupling. I don't know, which is why I am asking! (smile)
Sibrina
I'm not familiar with OLED chemistry, so I can't offer any advice in that area besides to start looking at the emission of known Re(V) oxo species, maybe with ligand frameworks similar to previous OLED systems (a ligand involved in a MLCT usually needs to be able to accept electron density...maybe check Re(O)X3(L) species where L is a bipy or something) Good luck, sounds like an interesting project.