January 2, Thursday
Fun with NMR and the Glove Box!
Intro
Excited about doing NMR
What is NMR?
All this shielding information tells things about the environment of the hydrogen atoms you're looking at. If they are near a particularly electronegative atom, such as N, O or S, that pulls away electron density from the proton nucleus, the proton will be significantly deshielded compared to an H atom that is not near one of these atoms, resulting in a different chemical shift value on the NMR.
This technique can be used to find the structures of small molecules, which is what we did at Oxford and it was the most fun thing EVER! If you're REALLY good at NMR, you can use it to find the structure of very, very small proteins - but that's much, much more complicated.
Predicting our structure
So, she walked me through that for our ligand. I got the number of distinct types of H's about right (I forgot that benzyl H's are in three groups though). I attempted to predict the shielding of the various H's, but I got a few of those misplaced too. She asked me - why do you think THAT one is more deshielded than THIS one? Due to her hints, I rearranged a two of them twice until I got it right. Then she told me to write down an estimate of the splitting patterns based on this which I did. To my happiness, she looked at what I'd written and said it looked good, in a mildly pleased/surprised voice. I was amazed I had gotten it right.
[Note: if more than one hydrogen atom is next to each other, they will "split" each other's signals in a distinctive way that can be predicted, thus giving more structural information.]
Photos of NMR samples and instrument for reference
Taking our samples
Fish was finishing up a sample when we came in. I asked Marika who puts the samples in the NMRs? Can we do it - can I do itttt?? *huge hopeful eyes* She said oh yes of course! But when Fish was done, she asked if we had a sample and put it in for us, to my horror, and I was heart broken, until Marika very kindly let me redo the whole thing and explained what Fish had done. Then I was SO happy! I got to put a sample into a fancy NMR instrument! Oxford's is super old - so old they let undergrads use it. >.> It's cool - the sample floats above a stream of nitrogen gas (I *think it's N2 gas ... O.o yes, yes, it really is! I checked).
Our spectra
I showed our spectra to Christian excitedly (he had been seemingly skeptical about the purity, but without an NMR, of course he should be). I was like - seeee?? PURE! HA! We did have a little bit of ether and water still left in our sample though. How did ether get in there, you might ask? That's a good point! And leads me into the NEXT section of my story here.
Final Analysis/Discussion of Our Ligand
Using the glove box! Miscellaneous Comments About It
Once, in the Weinert lab, no one was there and I sneaked my hand into a glove and pushed a jar in their glove box. Then I felt guilty and vacated and just stared at it. I wasn't sure I was allowed to touch it.
Aren't the puffy gloves funny looking? I've always thought so - like monster octopus arms waiting to slap or grab you as you walk by, or something. Usually when I walk by, I'll poke them. It for sure feels *really* weird putting them on, like I'm part astronaut. Or working in a BSL-4 lab with ebola! Something like that.
What We Did In the Glove Box
Those gloves are SO big! They're kind of hard to use, to grab things. Marika said she thought it'd be better if they had smaller gloves. Maybe so, but I still think part of the difficulty comes merely from feeling like an astronaut.
We let the reactions go overnight. And THAT was the end of Thursday! John and I had a relaxing evening. Pray for him to have more relaxing evenings - he's been having trouble getting stressed at the end of his evenings, without reason, and being so frustrated he can't just relax.
January 3, Friday
More NMR and Recrystallization!
Intro: start of day, reading & special treat of mocca coffee
Marika had left me peppermint mocca instant coffee from Starbucks for Christmas on my desk, which was SO sweet! (No pun intended.) So, today, I made some with whole milk I got at the CVS. I usually drink 2%, if it's just a little container and it's just for me, I almost always buy whole milk. It's a treat! Marika asked me today if I ever drank cream, like I drink whole milk. I said, why no, one doesn't drink cream. She said that *she* used to, when she was a kid, and sometimes, she still did - it was such rich, thick stuff. I know people who gag at whole milk, so I can't imagine what they would say to that - but I thought that was fascinating. Maybe I'll have to try that someday, at least once. That coffee was really good! I loved it. Then I made tea later. It was SOO cold today, I wanted to keep drinking hot things so I could be warm. When it stays 20F outside, I have trouble staying warm, even inside, especially since I sit near a window.
More NMR
We got a spectrum of my ligand that we'd dried extra overnight and also of her ligand that we used in the metallation reaction. She hadn't done an NMR of it yet, but she knew it was ok, she said, because she did it like all the other times she made it and she'd used it in a reaction and it worked like usual. The NMR confirmed her prediction of purity, except there did appear to be some acetone in there. Also, mine had lost the ether and water peaks. YAY!
Filtering our overnight reaction
It was fun to filter the reaction. We took it out of the glove box to do it. She said, if we had had to do it in the glove box, it would have been incredibly irritating and taken forever.
Scary 'near disaster'
Marika was so sweet and smoothly went about setting up a separatory funnel to separate the phases and making soothing sounds and comments saying, ohh, it wasn't such a big deal, maybe it would even be better this way! (Because water would dissolve our contaminant and also our more annoying solvent, while pretty much not bothering the rest of it.) O.o I've never met anyone but Marika who is so thoroughly and incredibly supportive, comforting and encouraging nearly 100% of the time, no matter what happens. She amazes me. I'm totally copying her, if possible.
Mistake #2
Recrystallizing the complex
I added different levels of ether to the three other vials and we stared at them for a while. It was kind of hypnotizing. The last one to which I added the most ether started making crystals after ~2 minutes. I was annoyed. It was making the feathery, not good kind. Marika had showed me these with her example vial. But she said it might turn out for the best in the end, because they started making some good ones after ten minutes. Very intriguing. The others didn't make crystals right away. We decided to let them crystallize over the weekend. Marika said that if they didn't make crystals by tomorrow, she'd add a little bit more ether.
Finishing Things Up
I asked Marika, if she was ok with pretty much just showing me things all day. She said, it was totally fine with her - right now - she was kind of taking a "mind break" from serious chemistry and trying to clean and reorganize things around the lab or at home, anyway, so she said nope - she was just hanging out with me. Somewhat amazingly convenient for me - she actually seems to like teaching, which makes me worry less about the bother I'm being. I pretty much have to have her help with everything, so far. Although, I did a few things today on my own, putting things in the glove box that she asked me to and setting up filtration flasks and stuff.
After finishing my notes, we left together around 8:30 p.m. We started talking about cookies. I mentioned that I planned on making some for the Warmachine crew. She told me about this amazing stuff called "peanut butter powder" or something. Apparently, it's a powder ... of peanut butter! And she said, she bet you could make peanut butter brownies with it! (!)
What a novel thought! I bet John would LOVE those. She said you could also just sprinkle it on cereal or anything that was hard to actually spread peanut butter on. *steeples fingers* I decided, I have to find some of this stuff and make peanut butter brownies secretly, see what happens and if they're good, surprise John with them. Yesss yesssss. *strokes non-existent beard* An evil plan is hatching!
FIN: making cookies at Brian's house
So I made cookies. And while I made them, I wrote this note, listened to their RP and ate a frozen french bread pizza (the other half of which I had for lunch). I was too lazy to go buy food. It was late, so I just wanted to go see John and make cookies.
I really enjoyed being here. I'm SO glad I came! I made regular and peanut butter cookies, which were devoured in less than 10 minutes. I made sure to warn that John better get peanut butter ones. He told me, upon my questioning him if he did in fact get any that yes, he'd eaten five. Good, good. John must have cookies.
I've really missed the Warmachine peoples. I can't remember having seen them in forever! I really do love them all. And that's the news today! I'm going home as soon as I post this, pretty much, after I clean things. I'm incredibly tired. Didn't sleep that well previously. Looking forward to weekend, doing some cleaning and hopefully, more reading! *crossfingers*
P.S. I showed Brian the glove box and he was like - cool - it looks just like in virus movies! And I was like, I know right? It totally does.