Yesterday, we completed the Baeyer-Villager oxidation of cyclohexanone. The remaining liquid was rotavapped to remove the dichloromethane from the solution and just leave the monomer. I really thought this machine as awesome! It does the same thing as setting up a distillation, but reduces the time of the process by an amazing amount. Rotavapping only took about 10 minutes; I'm not sure exactly how long the distillation would have taken for this solution since we didn't run it, but I can imagine at least 45 minutes.
After the dichloromethane was removed from the product, Kristin (a senior at College of Charleston who is also working with Dr. Van Horn) took me upstairs to show me how to run an NMR on my product. We needed to run the NMR to ensure that what we were left with was only the monomer and no left over chemicals from earlier in the experiment. The NMR looked pretty good except there was a peak between 5 ppm and 5.5 ppm. After some research, Kristin and I realized that this peak represented some dichloromethane that escaped the rotavap process. There was no peak for mCPBA, which was the main concern, otherwise we would have had to redissolve the monomer in dichloromethane, extract it again, etc.
To double check our result, Kristin and I tried to run a TLC, but none of my product moved up the column. We weren't really sure why this happened, but we just moved on since we already knew what my product contained because of the NMR.
We placed my monomer under a vacuum to remove the rest of the dichloromethane. Almost immediately I could see it bubbling off. After everything excess is removed from the monomer, I expect it to look extremely viscous and kind of rubbery (hey, it really is a polymer!)
I was going to start the polymerization of caprolactone with Tin in the MARS (Microwave Accelerated Reaction System), but there was an error message when we turned it on. Also, my chemicals won't be arriving until late this afternoon, so it sounds like it's something I'll get to start on Thursday.
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