r/Chempros

https://reddit.com/link/1uo83wa/video/6zk8jftq0gbh1/player

Hi everyone,

I've been working on a personal, open-source project to solve a recurrent issue many of us face: wanting to quickly inspect 1D FID datasets when away from the lab bench or during a commute, without needing to boot up a laptop just for a fast glance.

To tackle this, I'm developing a lightweight Android viewer designed to parse and render Bruker 1D data natively on mobile devices. The focus is purely on portability and exploring how standard NMR processing algorithms translate to mobile hardware constraints.

Current Technical Implementations:

• Data Parsing: Directly reading and parsing binary Bruker 1D FID datasets.
• Rendering: Real-time spectrum visualization optimized for mobile touch controls (fluid pinch-to-zoom and panning).
• Basic Workflow: Implemented automated height adjustment, peak picking, and solvent referencing.

Next Steps & Implementation Hurdles: The project is in early development, and I'm currently looking into efficient mobile implementations for:

• Interactive phase correction and baseline correction algorithms.
• Integration and multiplet analysis tools.
• Expanding to 2D spectra data structures.

Since handling digital signal processing for NMR data within a mobile framework comes with unique optimization challenges, I'd love to get some insight from the community:

1. If you were to quickly check a spectrum on the go to verify a synthesis step, what processing feature (e.g., specific apodization functions or baseline corrections) is an absolute dealbreaker for you?
2. For those who manage automated workflows or monitor reactions remotely, what kind of mobile interaction would actually fit your routine?

The project is fully non-commercial and aimed at providing a handy tool for the community. I'd highly appreciate any feedback on the feature set or technical direction!

GitHub:
https://github.com/S1lveric/MestreMovil

APK:
https://github.com/S1lveric/MestreMovil/releases

My lab is newish, and we've been ordering tons of instruments. Each time either something arrives missing or it breaks within a month. We were delivered an instrument without the several thousand dollar software we purchased, another instrument has been sent in twice now and it breaks within a week too. Our scale has an issue and it's a few months old, and it's going to take over a month for a technician to come in and look at it. We've had other stuff break or be delivered incorrectly. How do these companies all manage to suck this much? We're using them regularly as intended, and we're not even using some of them that much.

What's your ordering chemicals/accessories system? I feel like our is outdated and need to improve it.

I am a bachelors graduate in chemistry and got admission in Masters in drug discovery and development at University of Aberdeen, my goal is to work in pharmaceutical companies is the the path i am taking correct

Hoping that y'all have some advice. I'm working with some pretty volatile substrates (2-acyl tetrahydrofurans) that I synthesize using ethyl acetate as a solvent and purify by chromatography with ethyl acetate and hexanes. I've explored different solvents for both, but there really doesn't seem to be any getting away from ethyl acetate.

The problem is that I'm really having a difficult time getting rid of the last of the solvent in vacuo. I can get rid of 99% of the solvent without a problem, but NMR is showing residual solvent unless I rotovap it hot or long enough that I have substantial loss of yield. My guess is that the ethyl acetate is just getting stuck to the substrate by IMF. The material is a slightly viscous oil (think vegetable oil), so I don't think that the solvent is being trapped mechanically.

I'm working on a small enough scale the fractional distillation doesn't really make sense, so I'm hoping to liberate the residual ethyl acetate with an azeotrope or some other solvent shenanigans. Does anyone have experience with something like this?

I used some whink rust remover and followed precautions but then realized after taking off my yellow gloves that my fingers inside were damp and some of the product might have gotten on my skin in diluted amounts (my touching wet clothing that I squirted whink on).

After figuring that out I immediately put my hands under water for 15 minutes but I am still scared of risks because of another post and beyond that I can’t find much info.

I feel fine but seems like that doesn’t matter. Also there’s a chance my hands were damp before I put on the gloves. I really don’t want to go to the ER because I think it’s not a problem and of course that’s so expensive.

Does this seem like something that should generally be ok? Seems like the percentage is so low at 1.5-3% that it even undiluted wouldn’t be a huge problem?

Also the bottle is like 10 years old and I don’t know if that makes it better or worse.

And is soap and water the best way to wash that clothing because now I’m terrified of it.

Graduating with my degree in chemistry in 30 days and have been interviewing. I had a hard time at first and had some intense / almost humiliating interview experiences but also ones that have gone well.

Yesterday I received my first offer which is awesome. The role would be entry level chemist, at a fertilizer testing company. The pay would be around 19.50 / hr and he said a dollar more after like 3 months. It’s nothing crazy but honestly it’s the most I’ve seen so far.

The director of the lab and I talked for like an hour and a half and it went very smoothly and conversational and he stated he liked the conversation we had.

I’m very happy that I finally landed something, and the title of Chemist on the resume is a plus compared to other entry level titles.

However there are pros and cons to everything as you all know. The building of the company was built in the 1920s and that is clear. The vents are black, water damage across the walls, and a permanent time capsule of the 1970s design on the inside. The lab equipment and chemistry performed is legit and there are all sorts of glassware and machines, but the environment itself (at least from my memory of the lab during the interview tour) feels on par with a medieval cave.

Also, the staff there seemed nice but most people were in their 50s-60s who had been there 15+ years. Age obviously isn’t a problem, I have several older friends, and I make friends easily, but I do worry about a feeling of loneliness or isolation. However, I also don’t want to jump to conclusions.

I had some other possible companies on the hook but no official offer yet like this one. Those were lower paying lab tech jobs or sampling positions that had future possibilities to move into bench chemistry positions. Those jobs felt cleaner, more modern, and organized and had people there that seemed like (if I eventually broke that coworker-friend boundary) , I could talk video games / hobbies with and become friends.

Other than the general description of my situation, do any of you have any thoughts on all this, advice?

Or just advice in general as it relates to transitioning from a decade of restaurant work to my first job in the lab as a chemist.

Is the wage okay? How long does it take to feel confident?
Any tips on making a good impression?

Some of my interviews left me feeling under qualified and embarrassed tbh due to unexpected specific questions, I was able to answer a lot but also felt stupid as well lol.

Thanks for reading

Hi! My colleague is making some highly crystalline PVA and having trouble fully removing HFIP, water and methanol from the precipitated polymers. He's seeing the residual solvent by proton NMR and the blank doesn't contain any residual solvents.

As of right now he's tried:

1. Drying under high vac a week at 60°C

2. Drying under high vac for the weekend at 90°C

3. Re-precipitating to a finer powder for high vac drying

Any suggestions you all have on how to remove the residual solvent would be so appreciated! Thank you in advanced!!

I am a chem phd, used to wearing vans and NB in the lab. Just started summer work at a national lab and during training it occurred to me that I should probably get something made of leather or non-porous material, because I normally wear canvas (and have some acid bath stains lol). Any recommendations for maybe higher-end vans/NB/adidas that would be suitable for national lab standards but still comfy and “stylish” enough to wear around? I really don’t want boots.

So this is kind of a weird one. I was spaced out making internal standard right after my curve. I use scandium for my internal standard and multi element standard for the primary standard. I don't know if I accidentally poured scandium acid back into my primary standard container (I know not to pour things back in but I overpoured one of the liquids). I ran a curve, my curve is normal and my y-intercepts are 0.0. My ICV, CCV, and ICS all passed, so does that mean I don't have scandium contamination, and I'm psyching myself out?

Our lab is starting to replace some aging analytical equipment, and one of the instruments on the list is a chromatograph. New isn't completely off the table, but we're comparing it against refurbished systems to see whether the savings are worth it over the long term.

What I've found is that two seemingly similar systems can have a surprisingly large price difference. Some sellers provide detailed service records, qualification reports, and warranties, while others provide very little information beyond the model and configuration. I've also used alibaba over the years as one of several places to gauge what's available on the market, but it doesn't necessarily make it any easier to judge what's actually good value.

For those who've been involved in purchasing or maintaining chromatograph, what ended up being the biggest deciding factors?

Hi, I am trying to couple these two molecules. The first reaction I thought about was using a basic buffer like bicarbonate buffer. But I can't do this reaction in aqueous medium since the amine-containing molecule self assembles in water. The next reaction I thought about was using DMF with a base like DIPEA (to deprotonate the amines since many of them are probably in NH3+ form as they were isolated from a TFA-mediated deprotection reaction in the last step). But the NCS is most likely to get hydrolyzed in the presence of a base like DIPEA. The last option could be to use pure DMF without a base but I am worried if the amines are all in NH3+ state, they won't be nucleophilic enough to attack the NCS group. I just a few milligrams of the NCS-containing molecule so I can't set up multiple reactions and figure out a way via trial and error. I can perform two reactions at most. If it were you, which conditions would you try first? Or would you try something different from what I already mentioned? Tysm in advance!

https://preview.redd.it/j27xqiqyngah1.png?width=1150&format=png&auto=webp&s=5dbc941c921a891d3a1ec0c60f91b305c2338495

https://preview.redd.it/r0jqoiqyngah1.png?width=1504&format=png&auto=webp&s=42ffea4fd48b74a3ed087edffed43197813e6390

link: https://pubs.acs.org/doi/10.1021/acs.oprd.5c00349

doi: https://doi.org/10.1021/acs.oprd.5c00349

thanks in advance

Hey, I have a small question about silica deactivation for column chromatography. I found a procedure that says "After concentration, the residue was quickly chromatographed (20% EtOAc-dichloromethane, silica gel was de-activated with 35 wt% water)". I never needed to deactivate silica, so how much water to I really need? Is it, for example 65 g of Silica + 35 g of water (which seems very excessive) to get 35% of water in the end "product". Or is 100 g of silica + 35 g of water (which seems much more reasonable)?

Additionally, is it possible to deactivate my silica TLC plate to check Rf before running the column? I guess dipping into water and drying is too easy?

Thannks a lot!

Unsure if this is the most optimal place to post.

I am trying to find the best thing to use to purge water with N2. I have seen a lot of people use fritted glass and am curious as to how essensial this is to the process. Is there anyway to DIY or get a cheap one? Is nanometer essensial or could we make do with mm? We will be purging batches of approx. 1.8L for 30 mins. Currently the smallest we could go is 0.4mm, would this work?

We are trying to crudely replicate anoxic conditions of wetlands in our water samples and there will be high concentrations of arsenic.

https://preview.redd.it/35gptfcoix9h1.png?width=1063&format=png&auto=webp&s=65187f77077a47f5c28d55d179677f41755a11ff

Hello everyone! I am currently trying to reproduce reaction b in this scheme. It appears that the mechanism involves a lithium reduction of the enone to form an enolate, which is then trapped with TMSCl to yield the silyl enol ether, followed by a Mukaiyama aldol reaction.

However, I am having trouble trapping the enolate with TMSCl. The major product I'm obtaining is simply the saturated ketone (reduction of the double bond). Could this be due to trace moisture in my reaction environment protonating the enolate before silylation can occur? I even dry my ammonia gas from the ammonia tank by passing through a CaO column but the result is still unpleasant. I would greatly appreciate any advice or troubleshooting tips from anyone who has experience with this type of transformation. Thank you very much.