26 Jul Zoe Schiffer – Chemistry at TSRI – Engle Lab – Week 6

Hi everyone! Just a quick recap: my name is Zoe Schiffer, and I had the amazing opportunity to spend six weeks in San Diego interning at the Scripps Research Institute in the Engle Lab, led by Keary Engle. Throughout my internship, I worked closely with Madison Wagner, a fourth-year Ph.D. candidate, who served as my mentor. With that being said, my six weeks have come to an end, and I have learned so much.

This week, we performed an alkyne difunctionalization reaction. We started by weighing out the base in the glovebox. Since we were running three reactions simultaneously, we tripled the amount we needed. I still think the glovebox is something I’ll eventually become more comfortable with, but right now I find it challenging because there is so little dexterity in the gloves. After weighing the base, I returned it to storage and placed our materials in the antechamber so we could remove them from the glovebox. That process felt much easier than it did during my first week. That may simply be because I’ve had more opportunities to watch other people use the glovebox, but either way, I definitely felt more confident. I then weighed out the remaining reactants into separate vials, which took quite a while.

Next, we added the liquid reactants and allowed the reaction to stir for two hours. When we returned, we quenched the reaction, extracted the product, and filtered it. This process involved separating the product from the byproducts by carefully pipetting off the top layer of liquid. We repeated this process several times to make sure we recovered as much product as possible without wasting any. The collected product was then transferred through a filtration system to remove additional impurities.

After that, we ran a crude NMR to determine the reaction yield. This involved adding an internal standard—in this case, dibromomethane—to the product in a known amount. By comparing the hydrogen peaks from the dibromomethane to the aldehyde peak, we were able to estimate the yield of the reaction. One of our reactions gave a good yield, while another was not quite as successful. Normally, I would have used the prep plate method to purify the product, but we ran out of time.

This week I also attended the NSPIRE presentation practice. Madison presented her research and received feedback ahead of her presentation the following week. I had seen bits and pieces of her work throughout the summer, but seeing the entire project come together was really interesting, and it helped many of the concepts click for me. It also gave me some insight into preparing for my own wrap-up presentation, which I gave to the lab on Friday. Students from Cal State San Marcos were also visiting, so they toured both the Engle Lab and one of the biology labs. I joined the tour and can confidently say that I understand chemistry much better than biology. I also learned that I am very grateful I don’t have to work in a cold room! I can learn to use a glovebox, but working in a cold room doesn’t sound nearly as enjoyable.

I also had the opportunity to continue working on my presentation slides, which was very helpful. We were even able to update some of the information based on the reaction we completed earlier in the week. I also shadowed Wenji again as he worked on a reaction similar to the one he had done the previous week. For lunch one day, we all went out for hot pot since I had never tried it before. It was definitely a unique experience, and I really enjoyed it.

On my last day, I gave my wrap-up presentation to the lab, explaining the work I had done over the past six weeks. Afterward, we celebrated with cake that Madison had made because she couldn’t find a dairy-free one to buy.

Outside of the lab, we spent the week packing up and cleaning the house before heading home. There were definitely a few “spontaneous” trips to Cocobomb mixed in as well. I also went paragliding, which is something that I didn’t expect to love as much as I did. Overall, it was a pretty relaxed week, with some climbing, plenty of laughter, and lots of great memories.

I can’t believe my internship is already over. In some ways, it feels like it flew by, but in others, it feels like I was there for much longer. I learned an incredible amount, but I also realized just how much more there is to learn. I absolutely loved working in the lab, especially in the Engle Lab. The sense of community there was amazing, and I truly enjoyed being a part of it. I am incredibly grateful for this opportunity, and I can’t wait to see where it leads me next.