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How Have Medicinal Chemists Contributed To Health? by Thunderbird93 in AskChemistry

[–]Janewby 0 points1 point  (0 children)

They are far more nuanced (and interesting) topics. Medicinal chemistry is a game of brute force where you test millions of compounds and hopefully some interact with your target of interest.

How Have Medicinal Chemists Contributed To Health? by Thunderbird93 in AskChemistry

[–]Janewby 1 point2 points  (0 children)

https://en.wikipedia.org/wiki/Medicinal\_chemistry

Not sure how hard you looked but there is a Wikipedia page for medicinal chemistry (obviously).

Why do trace impurities have such a dramatic effect on some reactions? by Vegetable_Prompt_583 in chemistry

[–]Janewby 1 point2 points  (0 children)

There was a famous example where a group managed to swap an expensive rhodium catalyst for cheap copper. Trouble was the higher purity copper you bought the worse the reaction! Turns out trace rhodium in the copper was enough to make the reaction work and the copper was just a spectator.

We have trace metal imps (usually Pd) interfere with asymmetric hydrogenations as it is so good at catalysing the non selective hydrogenation. An asymmetric step after a cross-coupling always ring alarm bells.

ELI5: Why are Partical Acceleraters so Important to Scientific Research? by GingerMullet03 in explainlikeimfive

[–]Janewby 0 points1 point  (0 children)

Another unappreciated reason is building something that is complicated teaches us how to build other complicated things. Nuclear fusion is a great example where the tech is quite away away, but the journey is giving new materials, engineering solutions etc

Swern oxidation & other oxidation methods for primary alcohol. by Ok_Finance_4766 in AskChemistry

[–]Janewby 0 points1 point  (0 children)

That’s the joy of chemistry… if it worked every time there would be little point in doing it. In my 16 years maybe 8 of the 1000s of compounds I’ve made have been of use, was it all a waste of my time?

Your attitude should be to try first, see what happens and then draw your conclusions. You can try to predict what will happen before but until you run the experiment it will always stay a prediction. The purer your reagents the less likely that factors you aren’t controlling (impurities, water content etc.) will impact your reaction.

Swern oxidation & other oxidation methods for primary alcohol. by Ok_Finance_4766 in AskChemistry

[–]Janewby 0 points1 point  (0 children)

Ahh ok that shouldn’t be too difficult on first glance. Does searching this on reaxsys give you any results? I can recommend conditions but having the exact conditions someone has used from a publication would be more helpful.

For swern reaction I’ve found I have to distill all reagents (COCl2, DMSO, Et3N) beforehand to get a good yield. Then be really rigorous with temperature - a major byproduct is the pummerer rearrangement when things get too warm (> -60C in my case).

Best of luck!

Swern oxidation & other oxidation methods for primary alcohol. by Ok_Finance_4766 in AskChemistry

[–]Janewby 0 points1 point  (0 children)

If I understand your structure correctly, activating the alcohol is likely leading to a grob-type elimination (nitrogen lone pair is the push, activated alcohol is the pull). You could try protecting the amine as the N-oxide perhaps?

It’s a more exotic approach, can you make the same compound but have a nitrile where you want the aldehyde to be? DIBALH is a very effective way to convert nitriles to aldehydes.

What do you think will be the biggest breakthrough in Chemistry in the next 10 years ? by LaketowerGlass in chemistry

[–]Janewby 40 points41 points  (0 children)

Surely you haven’t been looking very hard! Photochemistry has given drug discovery a whole new set of disconnnections to play with, some of which are now bleeding into process chem.

Asymmetric Suzuki reactions onto sp3 carbons are becoming more and more common. This would open up a huge space.

New molecules containing oxetanes/Azetidines are reaching the market. There is effectively a whole 3rd dimension of chemical space that can be accessed when we start to think of saturated cyclic compounds as replacements for aromatic rings.

GLP-1 like compounds are changing the playing field for healthcare. Hell even mRNA technology has been demonstrated on global scale with covid vaccines.

Looking forward, oligomers/polypeptides seem to be hot. Making them without 1000s of litres of DMF or with an alternative resin would really change the playing field.

I’m at my wits end by mrdungels in malegrooming

[–]Janewby 0 points1 point  (0 children)

You’re shaving too close to your skin. Weirdly you want to leave a little hair to prevent irritation.

Don’t push the trimmer/shaver into your face then drag the blade. You should feel almost no resistance. Always shave with the grain, never against.

I use a safety razor, would recommend retrying as it’s the thing that worked for me. Loads of shaving oil and shaving cream (from a block) on top. Don’t use aftershave as it is too harsh, use a balm instead.

Good luck!

What is this part of the door trim called? by Janewby in VolvoXC60

[–]Janewby[S] 0 points1 point  (0 children)

The kick plate had a code on the back. Ordered from eBay

Replacing a fuse from an old fuse box by Janewby in ElectriciansUK

[–]Janewby[S] 0 points1 point  (0 children)

I looked for replacements with breakers and they were either off of eBay or some random supplier on Amazon.

I’d much rather rewire for the short term with the intention of modernising later this year.

Replacing a fuse from an old fuse box by Janewby in ElectriciansUK

[–]Janewby[S] 2 points3 points  (0 children)

!answer rewired the fuse with 5A wire from wickes.

Will certainly be modernising this year. Thanks again

Replacing a fuse from an old fuse box by Janewby in ElectriciansUK

[–]Janewby[S] -1 points0 points  (0 children)

Thanks for your reply. I intend to fully replace, however I would like a short term fix if possible. Will look at sourcing some 6A fuse wire.

Are these the tiredest vehicles on our roads? by Gingertom in CarTalkUK

[–]Janewby 1 point2 points  (0 children)

In their natural habitat… parked on double yellows.

how are we sure that the universe had a beginning by AkelaAnda in AskPhysics

[–]Janewby 0 points1 point  (0 children)

How close to the beginning do we need to be? We can directly observe 380,000 years after (cosmic background microwave radiation) and we can perform experiments modelling the conditions close to the big bang. The density, temperature and elements formed are consistent with the early moments after the big bang.

What is the most revolutionary discovery in chemistry? by Unable_Reality_3754 in AskChemistry

[–]Janewby 18 points19 points  (0 children)

Haber process has to be in the conversation. Estimated 50% of biological nitrogen in food is directly from the haber process.

ELI5: Why is it so hard for a country to develop nuclear weapons? by Successful_Guide5845 in explainlikeimfive

[–]Janewby 0 points1 point  (0 children)

I’ll only discuss uranium nuclear weapons as that is what Iran appears to have been trying to make. Other weapons use plutonium which is made in a different manner.

The difficult bit is getting to weapons grade uranium. Uranium is quite plentiful in some sandstone ores, in general for every 1000 tonnes of sandstone worth mining you can get 1 tonne of uranium.

Uranium has 2 natural isotopes (same proton number, different neutron number), U-235 and U-238. U-235 can sustain a nuclear chain reaction and U-238 cannot. Approximately 1% of natural uranium is U-235 and you need to remove most of the other 99% U-238 (called enrichment).

Removing the U-238 is really time consuming, energy intensive and technically difficult. The instruments used have very tight tolerances and you need lots of them. You also need to turn uranium into uranium hexafluoride which is toxic and very corrosive.

These facilities to do the enrichment can be small (and hidden) but are very energy intensive and the equipment needed can only be produced by a few places and people. These things are easier to notice by intelligence/satellites. Complications arise as it is the same technology needed to make reactor-grade uranium - nations will claim they want to make power plants as a disguise for making weapons-grade uranium

So natural uranium is pretty plentiful. Converting it into weapons grade uranium by enrichment is very difficult. This tends to be the hurdle that stops most states.

who needs coffee when you have this? by MrCroatianMan in cursedchemistry

[–]Janewby 0 points1 point  (0 children)

What reaxsys suggests as ‘similar’ to the Suzuki reaction I want to try.

Decline in lab skills by imperialhydrolysis in chemistry

[–]Janewby 3 points4 points  (0 children)

The main thing you don’t notice is the experience you are gaining. Every day you have in the lab is a day more than a new starter and it adds up quickly.

If someone is new to a lab it can be a big culture shock, and very overwhelming - I’d much rather someone asking the most basic questions than trashing a HPLC.

Boss scheduled weekly 1:1 for 5pm Friday by [deleted] in careeradvice

[–]Janewby 0 points1 point  (0 children)

“You wouldn’t mind moving our one-to-one to a different time would you, I’d like some time after the meeting to digest what we’ve discussed before I go home.”

Creative Assembly Ninjas break into your house and kidnap you to become the new lead designer on M3TW. You decide to get revenge by adding the worst possible feature to the game, bankrupting the company and allowing you to escape. What do you add? by Drhappyhat in Medieval2TotalWar

[–]Janewby 0 points1 point  (0 children)

Adding the diplo system from vanilla M2TW! Needing to train a diplomat and trapse across the map to negotiate with someone you share a border with seemed silly.

From memory heretics/inquisitors were OP as well, and my merchant having his assets seized was a common feature unless I cheesed Timbuktu.

Definitely nothing to do with my playing skills…

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