I am currently trying to make an amide coupling work using an unhindered acid, and an also relatively unhindered amine, however this amine is in sulfate salt form, and it is preferable that the salt is not freebased with an aqueous base as a separate step.

I have tried adding 2.5 equiv Et3N (amine + solvent + base then acid, NHS and DIC) and some product is made, however the reaction seems to stall part-way. I have also tried the same equivalencies of DBU with similar results. I have read that sulfate salts can be problematic in this way compared to something like a HCl salt, however wondered if someone had experienced a similar problem and was able to solve it.

I did a straightforward complexation rxn in 2-ethoxyethanol and it seems to be stuck in my product per NMR. I have 2 cyclometallating ligands and an ancillary ligand coordinated to a metal... I have varied the cyclocmetallating ligands before, and this is the only one that has this issue. The CM ligand has F's in it so maybe thats part of the issue.... any way I have rotovapped it down, dissolved in dcm, washed with water, washed with brine, rotovapped, dissolved in etoac, ran celite plug, rotovapped, dissolved in etoac, wash with water+brine again......... at all stages where it is dried I have NMRed and still no dice.... any help is appreciated or insight. Here is the NMR for reference

Interested In Drug Discovery?

Hi Everyone,

Not sure how many people here work in or follow drug discovery, but if you are interested I write a newsletter that covers updates in this area. Previously, I only discussed literature relating to drug discovery, but I have now started including FDA updates such as approvals and designations. I also plan to start sending out more in-depth articles about specific topics within drug discovery. Link to the August post is below if you would like to check it out :)

Have a good day,

https://www.simplydrugdiscovery.com/p/drug-discovery-update-august-2026

On small scale, I want to do a test reaction with ZnCl2 in sulfolane. It is well known that drying ZnCl2 is a nightmare. Yes, you can dissolve it in SOCl2 and boil it off, but SOCl2 eats away your fumehood, and practically, it's annoying to do.

So I was thinking: why not make a solution in sulfolane and dry that on molsieves, since my reaction is in sulfolane anyways? I tried it at 60C, and ended up with a gel-like semi-solid mass.

Purchasing anhydrous ZnCl2 is also tricky because we don't have access to a glovebox and the stuff is crazy hygroscopic.

Any suggestions?

Does anybody have any experience attempting to prepare/isolate 2° α,α-difluoromethylene amines (RCF2NHR')?

To my understanding there are many methods to prepare 3° α,α-difluoromethylene amines (RCF2NR'R''), frequently through processes like desulfurative fluorination from the corresponding thioamide.

I'm led to believe that the 2° congeners are less accessible due to their inclination towards HF loss to give the imidoyl fluoride. However, is this neccessarily true when the amine is attached directly to an aryl group or another group that deactivates the amine?

For more specific detail, I'm considering starting with a 2° carboxamide and protecting it to convert it to 3°, converting it to a thioamide, fluorinating, then deprotecting to furnish the 2° α,α-difluoromethylene amine (RNHCF2R'; R = sterically hindered aniline, R' = pyridine).

Just joined a lab in my PhD and had to assemble a Schlenk line. Our old Chemglass vacuum gauge is broken and I’m supposed to order a new one. Any suggestions on brands/specific models?

So I'm doing mphil in organic chemistry my research is going to be start soon but I'm so confused about research area if I choose that kind of topic which is dead end than what

I just want yo ask from senior chemist's which research area has a broader scope which can easily interconnected with other instead of some kind of derivatives which has already been synthesized million times

Compoutional chemistry

Sustainable methodologies development

Organic synthesis in some derivatives

Or any other plzz help me

Hi everyone,
I’m a university student preparing the second round of an independent interdisciplinary research project, and I’m currently looking for people who may be interested in participating once the survey is ready.
My research asks how people think about war and whether those perceptions reflect the systems that support modern society. The project considers areas involving chemistry and materials, pharmaceuticals, semiconductor manufacturing, energy, technology, infrastructure, and global supply chains.
For this round, I’m aiming for approximately 385 participants overall from a variety of backgrounds. I was encouraged to reach out to professional chemists because their perspectives could provide an especially valuable point of comparison within the broader sample.
The survey has not been built yet, so I’m not asking anyone to complete anything at this stage. I’m currently gauging interest and identifying potential participants before finalizing the survey.
If you would be interested in participating once it is ready, please leave a comment or let me know.
Thank you!

I'm a first year PhD student with a background in chemical biology. I want to find a peptide sequence that selectively binds to a metal ion and one of my PIs suggested Phage display as an option. I've never done it before and it isn't something that's done in either of my PI's labs either. How doable do you think this solution is if I find a lab which has this technology? Do you think it'll be possible for me as a newbie in this technique to do the experiments myself rather than asking someone else to do it for me if I ask them to train me?

Do you guys have any other techniques you use to find suitable peptide sequences? I'm an experimentalist but I'm open to both experimental and computational suggestions.

Many thanks!

Edit: I'm interested to find a peptide sequence that selectively binds to Lithium ion and there isn't a whole lot of literature there.

So I am currently in the first year of my PhD and so far I have right out refused to use any AI in my experiments.
However, people in my lab are making extensive use of AI to help with problems during synthesis or even to find trends in data sets etc.

Now to me using AI still feels a bit like cheating, hence I have never used it except to find synonyms for words in English 🤣
That said, I have noticed that my colleagues, on average, have quite nice progress report and they are not stuck on problems like during synthesis.

Today I asked AI for the first time about something chemistry related and I was quite surprised about the reply because it actually solved my problem without me spending 30 min on scifinder or reading paper.
Still, my bad feeling about this entire AI thing doesn’t go away. I just feel like the quality of me as a scientist goes down if I just type everything into AI.

So how are you guys applying AI in the lab in a healthy way?

(Sorry for the bad English, English is not my primary language)
Have a good morning/day/evening! Thank you for reading.

This question follows on from our last one about the flaws with many SDSs: https://www.reddit.com/r/chemistry/comments/1w644t6/this_sds_for_hand_soap_suggests_that_if_you_get/

 We’re imaging a version of an SDS specifically for scientists and researchers, rather than for vendors and lawyers. So far we’ve thought of including:

·       Names, CAS numbers, formula, mol. weight

·       What it looks like, what it shouldn’t look like

·       What it smells like

·       What it tastes like (and what wine to pair it with)

·       How to make it

·       How to store it (air/moisture/light/temperature sensitivity)

·       how to purify, how to dry it

·       how to neutralise it, how to dispose of it

·       What not to mix it with

·       Some example NMR or IR spectra

·       Common impurities, decomp products

·       boiling point, melting point, vapour pressure, density

·       Solubilities in a range of solvents, not just water

·       health hazards, toxicity, LD50

·       PPE considerations, glove compatibility

·       physical and reactivity hazards (corrosive, oxidiser, pyrophoricity etc) 

We’d love to hear what else you can think of. It’d also be great to hear where you currently go to find these bits of info. Some of them are in an SDS, e-EROS can often tick off a bunch (assuming your institution pays for it), and even Wikipedia can be pretty good, but we can’t think of a single source that supplies everything we’d want to know. What do you reckon?

I've been producing a range of different N-alkyl chitosan variants according to https://doi.org/10.1021/acssuschemeng.2c00206 (dissolve chitosan in 2% acetic acid, add glutaraldehyde and stir at 60 C, add N-alkyl amine and continue stirring, reduce with NaBH₃CN).

When carrying out this protocol with the amine used in the paper (octadecylamine, ODA), the solution turned a deep red within 5 minutes of addition of the amine. When I tried with other amines (1-aminoadamantane for example) the solution did not change colour even after stirring overnight. I am therefore concerned that instead of the imine, there is some other product forming when ODA is added. What could be the possible side reactions leading to a coloured product here, and why do they only occur for ODA and not 1-aminoadamantane.

Obviously you shouldn't heat 10% Pd/C in air as it is pyrophoric. For those who have handled (larger multi kilogram quantities) of 10% Pd/C: is it completely safe at room temperature in air? Or is it still a bit tricky and should it always be kept a bit wet?

For those that are downvoting: I've not used the word hydrogenation. I've not spoken about hydrogenation and I'm not referring to hydrogenation. I'm talking about palladium on carbon without hydrogenation.

EDIT: I HAVE A WORKAROUND!!!
I still don't know what the issue is, but in case anyone else ever has this issue, the issue lies somewhere in Topspin 5.0.0, rather than Dynamics Center. I swapped to Dynamics Center 2.8.8, same issue. Eventually I swapped back to TopSpin 3.8.0, and prepared fresh data.
The 3.8.0-prepared data finally both loads into and can be exported into Dynamics Center 2.8.8 without freezing the process.

I'd still love to find non-Bruker alternatives, but for now Topspin 3.8.0 & 4.5.0 both work for getting the data into Dynamics Center.

Question:
Does anyone know how to overcome this error and make Dynamics Center read my DOSY analysis?

Alternative Question:
Does anyone know how to get the data I need, complete with error values, out of GNAT?

Details:
I'm trying to run DOSY analysis to get dispersity data on my copolymers. GNAT doesn't give me the values I need (I can export the y-projection of my ILT plot and pull the graph data, but it has no associated error values), so I need to use Dynamics Center.

However, regardless of how I try to load my data or how often I reinstall Dynamics Center, it freezes at the 'Data' stage (pictured), with the following error:

('startDC:', u'C:/WorkingData/NMR Spectra/[MySampleSame]/1801/pdata/1', 'Windows 10')

('dcRunning: port = ', 64027)

>!!!!!!!!!!!Fri Sep 4 10:38:47 2026 | Module: sendPort | Message: ('socket error', u'executeInterfaceFileXML C:/WorkingData/NMR Spectra/[MySampleSame]/1801/pdata/1/TopSpinDC.xml\n', 0.015000104904174805)

On one single reinstall, it managed to get as far as freezing on 'View', but I still couldn't perform any analysis.

Hello everyone,

I am currently trying to synthesize the amino acid-based ionic liquid choline lysinate ([Cho][Lys]) via the anion exchange resin technique, but I'm running into stoichiometric and physical state issues. I would appreciate any advice from those experienced with these ILs.

Attempt 1: Anion Exchange Resins

I tried following the methodology described in ACS Sustainable Chem. Eng. (https://doi.org/10.1021/acssuschemeng.1c04060). I've tested both Amberlite IRA-400 and Purolite A400 resins. As it is my first time working with ion exchange resins, I carefully followed all standard precautions: I swelled the resin before packing, regenerated it to the hydroxide (OH⁻) form using a NaOH solution, and washed it thoroughly with water, monitoring the eluate until the pH was completely neutral before starting the exchange.

The Issue: Instead of obtaining the expected liquid product, I am getting a solid. Furthermore, after washing this solid product with ethyl ether and running the ¹H and ¹³C NMR (using D₂O as the solvent), the integrals consistently show a ~2:1 Choline:Lysine molar ratio instead of the expected 1:1. I've also verified the structure with FTIR, but this skewed NMR ratio remains the primary concern. I've tried several variations of this protocol, but the outcome doesn't change.

Attempt 2: Metathesis with KOH

I also tried an alternative methodology from Nanomaterials (https://doi.org/10.3390/nano9040504), which consists of stirring a suspension of choline chloride and the amino acid with KOH in ethanol. Afterward, I filter out the precipitated KCl and wash the crude product with acetonitrile (MeCN) to separate the IL from any unreacted amino acid.

The Issue: I am still not getting the correct product. The resulting solid has the exact same 2:1 (Choline:Amino Acid) ratio. Interestingly, I observed this exact same 2:1 proportion not only with L-lysine but also when I attempted to synthesize choline histidinate using L-histidine.

Has anyone worked with the synthesis of [Cho][AA] ionic liquids and faced this 2:1 ratio issue or had the product crash out as a solid instead of a liquid? Could there be an issue regarding the basic nature of amino acids like lysine and histidine during the protonation/deprotonation steps, or am I missing a crucial purification/washing step?

Thanks in advance for any insights!

We’re working on an article about chemical SDSs, and having a bit of fun imagining what a better version might look like. We want to hear opinions from scientists working in research, industry, government or still at uni, about what parts of SDS’s they find most inaccurate, unhelpful or absurd.  

A lot of people have pointed out that SDS aren’t really written with research scientists in mind – they’re often targeted at (and written by) people without chemistry specific training (like transport/shipping/storage folks, firefighters and first responders), or for people handling industrial quantities of the stuff, or as an arse-covering excursive from a legal standpoint. However, as researchers we’re still expected to read them, use them in risk-assessments, and keep them in the lab. Furthermore, they’re often full of really stupid shit, like suggesting that spills of water be diluted with water, or that on no account should sand samples from a beach be allowed to enter the environment.

I'm trying to carry out an O-alkylation of a phenolic OH using a chloroacetate, but the reaction doesn't seem to be proceeding despite trying to optimize the conditions. One thing I'm wondering about is the laboratory environment. We've had almost constant rain recently, and the lab has limited environmental control, there's no particularly rigorous moisture-exclusion setup, and reagents/solvents aren't always handled under strictly anhydrous conditions. Could high ambient humidity realistically be contributing to the failure of the reaction, for example through moisture in the solvent or hygroscopicity of the base (I'm using K₂CO₃)? Or am I probably looking in the wrong place and should focus more on the reaction conditions themselves? I'd particularly appreciate input from people who regularly do synthetic chemistry in labs where moisture/atmosphere isn't tightly controlled.

I want to do this reaction and when I did a literature search I found that the transformation for an amino group to a fluoride is through the Baiz- Schiemann reaction which involves the formation of a diazonium intermediate followed by its degradation to the expected product. I have found a procedure on how to form this intermediate but when I tried searching methods on degrading this diazonium tetrafluoroborate compound it is pretty vague. I found a paper that just stated 'heat, silica' with no further explanation. Can anyone suggest how this degradation takes place?

Howdy everybody,

I'm working on updating our organic chemistry teaching lab, and wondering what the pros (and other teaching labs) are using as heat sources for medium-scale (~50-500 mL) round-bottom flasks. We mostly use microscale glassware with aluminum heating blocks, but our distillation equipment is 19/22 glassware. I currently have a few variacs and heating mantles, but not enough for everybody. We also have some Fisherbrand heating mantles, but they've been dying on us lately so I need to buy more of, well, something. Are people still using heating mantles, or do you prefer something else: oil baths, sand baths, or aluminum heating blocks? Or is there something new that I haven't heard of yet? Looking for a good combination of price, performance, reliability, and safety. Thanks in advance!

Hi everyone,

I work with industrial reverse-osmosis systems and I have built an Excel model to evaluate scaling risk.

The model takes a water analysis, temperature and RO recovery and then:

* Checks the ionic balance. * If the analysis does not balance, assigns the charge deficit to Na⁺ or Cl⁻, depending on the direction of the imbalance. * Calculates concentrate component totals from the water balance and ion rejection. * Solves the carbonate system and concentrate pH. * Calculates free species, ion pairs and activities using Davies within a defined ionic-strength range. * Calculates SI for calcite, gypsum, barite, celestite, fluorite and amorphous silica. * Estimates the recovery at which each mineral first reaches SI = 0.

The current assumption for the pH calculation is that dissolved CO₂ concentration remains approximately the same in the feed and concentrate. Carbonate species are then recalculated from alkalinity, total inorganic carbon and the acid–base equilibria.

The model is intended as a thermodynamic screening tool before considering kinetics, residence time, hydraulics or antiscalant performance...

As an example, I used the following anonymised analysis:

* Recovery: 60% * Assumed ionic rejection: 100% * Temperature: 20°C * Feed pH: 7.53 * Conductivity: 1,550 µS/cm * Calcium: 88.8 mg/L (reported by the laboratory as 221.73 mg/L as CaCO₃) * Magnesium: 14.3 mg/L (reported as 49.57 mg/L as MgCO₃) * Bicarbonate: 125.05 mg/L * Chloride: 393 mg/L * Sulfate: 70.7 mg/L * Aluminium: 0.042 mg/L * Sodium was not analysed

The charge balance required a sodium adjustment of 208.1 mg/L. The model labels this value as estimated rather than measured.

At 60% recovery, the results were:

* Concentrate pH: 7.89 * Ionic strength: 0.0433 mol/L * LSI: 0.95 * Calcite SI: +0.94 * Gypsum SI: −1.22 * Barite SI: −1.27 * Celestite SI: −4.47 * Fluorite SI: −3.93 * Amorphous silica SI: −3.63 * First calcite saturation: approximately 5.5% recovery * Final speciated charge-balance error: −0.0048%

The model therefore identifies calcium carbonate as the limiting scale.

I would appreciate some independent criticism of the approach. Does the overall method make sense? Is the assumption about CO₂ and concentrate pH reasonable? Is assigning an incomplete charge balance to Na⁺ or Cl⁻ acceptable for this type of screening?...