Monday 10/16
Worked up bromination step left over fall break. Tar everywhere, covering everything. My PI (principal investigator; professor) needed to get hydrofluoric acid to clean the glassware afterwards.
Tuesday 10/17
Attempted nitration of 8-Bromonaphthalen-1-amine to 8-bromo-1-nitronaphthalamine. This procedure involved dissolving the 8-Bromonaphthalen-1-amine in 12mL glacial acetic acid, which was reacted with sodium nitrite and sulfuric acid. Diethyl ether was added to percipitate the diazonium salt. The Diazonium salt was oxidized into the nitrate in an equal-weight mixture of copper (I) sulfite and sodium nitrite. The resulting mix was left to stand for a few days. The procedure was rushed and did not end well.
Wednesday 10/18
I found an old bottle of 48% HBr (hydrobromic acid), with about 500 mL of the most disgustingly orange HBr I've ever seen in my life. I decided to do a large scale distillation of the HBr in preparation of the bromination of the 1,8-napthotriazine. I somehow gaslit myself into thinking the BP of the HBr-H2O azeotrope was ~156 C when it was actually ~124 C. I ended up screwing up the distillation and had to come back to the lab at 19:00 to restart the distillation. The second distillation was clean, with ~450mL HBr azeotrope.
Thursday 10/19
I synthesized n-butyl nitrite from n-butanol, sulfuric acid and sodium nitrite. Mixing the n-butanol, sulfuric acid and some water, I added this into sodium nitrite solution cooled below 0 C. I tried to keep the temperature down, but I also botched the reaction, scaling the n-butanol only 2x instead of 2.5x like I intended to. The reaction still worked, with a volumetric yield of ~65% compared to previous runs of 25% and 45% yield, but nowhere near my professor's reported yield of >90%.
I installed an aspiratior in a fume hood. That fume hood had 2 water lines and no other lines, so I replaced a water line with a vacuum line by connecting an aspirator to it. The aspirator pulls a 10mmHg vacuum, compared to the house vacuum's 100-140mmHg, a 10x stronger vacuum. This makes certain workup steps go a lot faster, including vacuum filtration involving fine particulates.
Friday 10/20
I vacuum distilled the 8-Bromonaphthalen-1-amine with the newly installed aspirator. I dried the product under the high vacuum (1mmHg vacuum).
We also got a new refrigerator, which I helped my professor install and fill. Considering how our old refrigerator has been dead for over 3 weeks, we desperately needed a new one to store the horrendous volatile chemicals in our lab.
I got to play with mercury, I cleaned and calibrated 2 vacuum gauges to measure the strength of the house vac and aspirators. Using nitric acid, I removed the oxides in the vacuum gauges and refilled the gauges with mercury. Now they both work.
Afterword: It's kinda hard to do Chemistry when the NMR machine is down. Organic chemistry is predicated on looking at some squiggly lines determined by the radio return of a jiggling hydrogen atom. This is how we see if things have changed, when all the product is a tar, sludge, oil or (on a very good day) crystalline. This week was mostly a preparatory week for the next week, as I prepare another synthesis attempt to make 8-bromo-1-nitronaphthalamine. I am going to get it to work, and it will be better the third time around.