/sci/ - Science & Math

>>8437176
I'm just a resin chemist I cant' solve this problem because I don't deal with inorganic chemistry

>>8437184
alright then calculate some flory distributions

>VN
>anime
The adaptation was crap. This is insulting

>>8437190
yo lad what do i know my favorite anime character is this one

>>8437189
I don't do any math at my job tho

>>8437192
TONI!

post stamps

>>8437198
God damn it biochemists you can't just write 'reduction' and get a enantioselective product

>>8437204
what is this lanthanide shit?

>>8437210
Found the article

its from some boring assignment I had a couple of years ago

http://pubs.acs.org/doi/abs/10.1021/om301010m

Lanthanides are fucking useless

>>8437230
>lanthanides are useless
any more useless than any of the other metals?

>>8437285
No ammonia without iron, lad

>>8437210
>>8437230
>>8437285
There are probably lanthanides in the machine you are using to view this post.

I'd argue that the actinides are far more useless.

>>8437336
This sounds like a contest with no winners

>>8437336
>probably

Aside from neodymium for hard drive magnets what ones?

>>8437539
https://en.wikipedia.org/wiki/Lanthanide#Applications

Yttrium for lasers and high temperature superconductors. Samarium for magnets. Erbium is used in fiber amplifiers. Gadolinium is useful for magnetic refrigeration. Cerium is used in lighter flints. Lanthanum oxide is used in fluid catalytic cracking. So basically a bunch of applications.

Most are luminescent, fluorescent, glow in the dark, all that jazz. Making them useful for phosphors. Pic related

>>8437176

yea OP, it's not a very hard problem
did anyone try this?

>>8437204
>biochemists you can't just write 'reduction' and get a enantioselective product
of course they can, b/c it's carried out by a chiral enzyme

Pls help
>>8437967

>>8437176
Looks like a M6 helicene. Next?

>>8438223
Nope

>>8437676
Yep


>>8437853
That's a classic

>>8437630
yttrium isnt a lanthanide

>>8437630
>lighter flints

Fucking lanthanides

>>8437230
For some Lewis Acid chemistry, lanthanides are uniquely effective. This goes double for asymmetric catalysis, wherein the energetic margins are so small (most times less than 2 kcal mol-1; in exceptionally selective reactions these values approach 2.8 kcal mol-1) that the "right" Lewis Acid is necessary for high selectivity.

>>8437230
>>8438490
Cerium trichloride is useful for the Luche reaction, and in Grignard reactions with some ketones that are, without the CeCl3, easily deprotonated in alpha position by the Grignard reagent instead of being alkylated. Samarium diiodide can be used for the barbier reaction and for various kinds of reductions.

>it's an "anon spills 75% of his reaction mixture on the bench and has to to the final step of the synthesis on 50 mg of compound" episode

Could be worse I guess, at least I'm not a natural products carbohydrate chemist

>>8438683
>wipe it up with a paper towel drenched in acetone
>put in glass frit; fill frit with acetone to let the paper soak
>pull vacuum to remove solvent
>rinse and repeat 3-4 times
>rotovap down
>repurify compound

>>8438614
Good call on stoichiometric lanthanides. I guess you can also include Ceric Ammonium Nitrate reactions (and the TLC stain CAM I guess?) as more practical applications.

>>8438700
>>wipe it up with a paper towel drenched in acetone
>>etc

m8 of course I did try that, but it was a carboxylate and I think it probably all just stuck irreversibly to the paper towels.

>>8438706
Then try washing it out with dilute acid to protonate it so it'll leave with the mixture? At this point you've literally nothing to lose by trying m8-E

>>8438712

It's too late anon, it's in the garbage can now

RIP heterobiaryl compound

>>8437176
>>8437676
A few questions:
-Doesn't copper normally coordinate 'octahedrally'?
-Wouldn't the linear pieces be offset in general, leading to a ladder or chain-like structure?

>>8438890
>-Doesn't copper normally coordinate 'octahedrally'?
because it's Cu+ (one plus)
>-Wouldn't the linear pieces be offset in general, leading to a ladder or chain-like structure?
I had this idea myself, probably the cluster thingy is more stable because it's more nifty-looking

>>8438890

Cu(I) is happy in a tetrahedral environment, it's quite small so perhaps it has trouble getting 6 ligands around it.

You are right that you could get polymers as well as discrete capsules, but entropy favours the formation of a lot of small species with many degrees of freedom, rather than a big polymer chain that is more restricted.

>>8437630
>Yttrium
>lanthanide

>>8438890
>Doesn't copper normally coordinate 'octahedrally'?

Naw, because in ligand-field theory it's d10 and thereby orbital splitting doesn't come into play. Therefore it can only bond via its s and p orbitals thus making it tetrahedral only (much like carbon)

>>8437676
>File: 1472325621243.jpg (911 KB, 1468x706)
looks like a titty fight.

>>8437868
But isn't every enzyme chiral? Why should specific enzymes suddenly become stereospecific?

>>8439966
For the exact reason you just gave: that all enzymes are chiral. It's incredibly rare that both enantiomers of a chiral molecule have equivalent bioactivity; as a consequence, enzymes are incredibly stereoselective (not stereospecific, but close) because they only really need one of the two enantiomers in the first place. Therefore, the enzymes that survive evolutionary duress are the most efficient ones -- i.e. those that are most selective for the desired product.

>>8440474
>stereoselective (not stereospecific, but close)
Reminder stereoselectivity is about the products and stereospecificity is about the reagents

This probably isn't the thread for this but where would one get started in self studying chem?

>>8440782
"Chem" is pretty broad

I got a decent set of intro to general, organic and climate chemistry lectures but they are in Dutch

https://www.youtube.com/watch?v=tR0MX9hethM&list=PLZ0df6wQ5oO_7cnWpPbt6pMjBpJyMLByb

You should be more specific to keep it interesting, just general chemistry is too boring imo

>>8440782
>>8440971 seconded
it is in fact pretty broad
I suggest you start with genchem just to grasp basic logics, then venture onward to:
pchem - if you like rigour and shit
ochem - if you like zigzags and curly arrows
aaand I don't have any significant experience in other branches really, mostly because they are not much interesting

>>8441003
Biochemistry is alright if you are just looking for a hobby. Lots of reading possible, and the lab work is the most boring part

>>8440782
Start with Oxtoby for gen chem, get familiar with some thermodynamics, and then peak around at whatever interests you. Everything will be boring until you reach near the end of thermo

>>8441107
Thank you all I just got back from the store with some notebooks to write some notes while I watch this videos.

>>8441193
Make a throw away email account and post it please

My first publication today! Only Chem. Comm., so not that incredible, but exciting for me. How's your research going, /sci/chem?

>>8442269
Waiting for some things on the lab to be fixed so I can finish the last part of my final assignment in my bachelors degree which should lead to a publication

but I'm a patient man, havent even finished my masters yet so why worry about publications

>>8440525
Yeah, that's why I said stereoselective you shit. Normal asymmetric catalysis has a huge disparity between selective/specific, but in enzymatic catalysis many enzymes are incredibly sensitive to the configuration of the starting material (see: any enzymatic kinetic resolution) so they are oftentimes best described as stereospecific. It's cool you know about definitions, but lame that you don't actually know dick about the chemistry at hand. :^)

>>8442269
Good for you! Keep doing science and keep publishing.

what's the order in which one has to learn chemistry topics? stuff like organic. analytic, and, uh, other stuff?
t. nonchemfag

>>8442466
Start with general chemistry for sure. Typical curriculum then moves to organic chemistry, then physical/quantum, then inorganic. I'd probably swap physical/quantum and then move into organic and lastly inorganic.

>>8442466
You're gonna need to complete calculus 1-3 before pchem And quantum/advanced orgo and stuff

I'm not doing very well in orgo (in my second quarter now) though I got top grades in gen chem (I know). Should I switch out of chemistry or will I like physical or inorganic more? At my school I can switch to a physical chemistry track and never take orgo again. I'm reading a book about chemistry and group theory and it's pretty interesting. But if the rest of chemistry is too similar to orgo I think I should go do a brainlet major...

>>8442637
just get good faggot

>>8442637
If you enjoy chemistry, stick it out

currently brushing up stoichiometry for med school, came across this:

How the fuck does he get 125g?
The balanced eq should be:

B2H6+ 3 O2 > 2 HBO2 + 2 H20. I use rounded AU values for B(80), H(1) and O(16)

From there on I went 36,1g/166mol = 0,217g/mol.
(0,217g/mol * 3)* 32mol= 20,887g.

What am I doing wrong?

>>8442637
What's your problem with organic? It's possible you're just being taught badly, or trying to learn in the wrong way. Organic's kind of weird in that you have to memorise a bunch of semmingly unrelated reactions until at some point it all clicks and you get how reactivity works (obviously there will always be exceptions). That knowledge is relevant to all of chemistry, but organic chem is how you get there.

>>8442637
I've heard that if you're good at genchem, you'll be shit in o-chem and vice versa. For me, that was true also.

Synthesis time! Your goal is to synthesize DL-Leucine starting with Diethyl a-bromomalonate. If you want, hard mode: no potassium phthalimide.

Fucking biochemists, cant you just write reduction and move on

>>8443564

How's this?

- Darzens condensation between diethyl bromomalonate and 2-methylpropanal
- Heating with aqueous acid hydrolyses the esters, decarboxylates, opens the epoxide at the reactive alpha position, and causes elimination of the diol to an alpha ketoacid
- Leuckart reaction converts the ketone to an amine using ammonium formate

Fucking wish I had chemdraw rather than this shitty free ACD thing.

>>8444334
isis/biovia draw is nice and free

>>8443564
>potassium phthalimide

Gabriel synthesis is for scrubs, why not just substitute an azide group and use the Staudinger reduction?

>>8443564
>no potassium phtalamide
k i use sodium phtalamide :^)

>>8444393
>Gabriel synthesis is for scrubs
ebin

>>8444393
>substitute for an azide group
I think in this particular case, you would get an imine group instead. Pic related is what i have in mind.

>>8444522
forgot pic

HELLO CHEMIST FAGGOTS
the chem building is right next to my math department, and I happen to need about a liter of isopropyl alcohol.

is it tacky / creepy to ask some girls studying chem there if they can get it for me? do you generally have loads of that stuff standing around?

>>8444554
They literally offer the azeotropic 90% isopropanol in stores. Just get out of your basement

>>8444569
when I google "isopropanol" I get a chemistry shop that sells 6 liters for 20euros and a drug store that sells half a liter for 5euros.
neither is what I need and Im almost sure they dont sell this stuff in supermarkets here in germany

>>8444588
>Im almost sure they dont sell this stuff in supermarkets here in germany
In America we have 70% and 90%, I'm sure Germany has something similar. In the end you can always run some fractional distillation if you want to reach a higher concentration.

>>8444524

Azides don't just lose nitrogen like that, the way you've drawn it you'd be generating a nitrene with 6 electrons rather than a deprotonated imine.

>>8444524

>>8444617
>pentavalent carbon
what the fuck

>>8444617

You fucking muppet

>>8444641
I'm just pointing out what >>8444524 made

>>8444655
checked

>>8444661

What he drew is completely legit, the ester is enolised. The red proton in >>8444617 was removed to make the enolate.

>>8444610
>>8444524 here, i drew some arrows to visualize what i imagine would happen. If a nitrene is generated instead, wouldnt the next thing that happens be electrons moving from the enolate group to the nitrogen (ultimately generating the same nitranion) so nitrogen can get its octet back?

>>8437176
I forgot to do my sapling learning quiz for chemistry. Is there any way to extend the due date from student access?

>>8444773

Looks plausible in the pic, but whether it actually happens is another matter.

>>8444773
>>8444955

I found this book in a Google result, from reading around it seems like alpha azidation of enolates is a fairly common method, so clearly they don't spontaneously lose nitrogen.

I wish I had a more comprehensive explanation, my best hand-waving attempt would be that you don't ever see fragmentations across an atom that already bears a formal negative charge, it's asking a lot for the enolate to push even more electron density onto that nitrogen. The enolate is actually already very stable being delocalised across both those ester groups, so it probably doesn't even "want" to extrude the nitrogen.

>>8443564

I sure hope this anon is going to come back and give us the answer or at least explain the choice of starting materials.

>>8444334
Would Darzens even work here? Because it would involve SN2 on a tertiary carbon, which doesnt usually occur.

>>8446239

It's intramolecular and highly activated, though.

>>8446239
>>8446243

Having thought about it some more maybe an alternative route could be:

- Generate the Reformatsky reagent by treating diethyl bromomalonate with Zn
- React it with 2-methylpropanal
- Reduce out the OH using Et3SiH in TFA or some other deoxygenation method
- React just one of the ester grops to the acyl azide with 1 eq. sodium azide, then do the Curtius rearrangement and hydrolyse the other ester

>>8446157
I wanted to bump this thread so I decided to post a broken question

>>8446278

How is the question broken? I think either of the answers so far would work.

>>8446282
>How is the question broken?
Post Gabriel synthesis question and at the end decide to exclude the reagent used for such synthesis. Technically, this isn't a broken a question; you're correct. Also, I don't have any answers for this question. I decided to see what cute things /cg/ could do with respect to α-amino acid synthesis.

>>8444554
are you retarded

walmart probably sells isopropanol, it's a disinfectant.

>>8446302
>math department
Probably

>>8446157
>the answer
There are of course many correct answers, as always when you have a synth question.
>>8446250
>reduce out the OH using Et3SiH in TFA or some other deoxygenation method
might reduce the ester groups aswell, if it does there are surely other ways to get rid of the OH, but i found a more convenient way:
-react Reformatsky reagent with 2-methylpropanal and base to get a Knoevenagel kind of product
-reduce the C=C double bond with Strykers reagent
-proceed with sodium azide and Curtis rearrangement the way you described

>>8446377

Shit, it's incredibly obvious actually to just reduce a double bond rather than try to deoxygenate. I can't say I've ever heard of Stryker's reagent and would have just gone for something obvious like Pd/C and hydrogen.

The Amazing Mr. Circle !

>>8446418
>palladium

WHAT IS the job market for chemist like?

I'm currently finishing undergrad. I want to pursue graduate studies but I read absolute horror stories about grad school and how there is absolutely no light at the end of the tunnel, only death and the permanent smell of of DMS.

What do?
Current grad students, how is your life? Are you happy?

>>8437176
Can anyone comment on these (synthesis of testosterone and its esters).

Are these guys even close?

I have a basic understanding of chemistry - what would I need to learn to be able to do this?

What raw materials are going to be a problem?

For personal use. I live in <country> where even if you need testosterone replacement, you can't get it.

https://www.elitefitness.com/forum/anabolic-steroids/synthesis-testosterone-dhea-your-kitchen-counter-662191.html

https://thinksteroids.com/community/threads/process-of-making-testosterone.134361616/

How to find out how legitimate pharma companies make this? Is it a trade secret?

>>8437539
>>8437630

Also, Gadlinium complexes f.e. with DOTA for MRI in humans. Cerium used to be used for redox titration. All of them for general magnetism jazz in intermetallic phases, though you pretty much covered that.

>>8447383
I want to know this soon.
Would different areas, like materials vs organic,be better than others?
I'm interested in stuff like nano medicine, biophysics/biochem, or molecular machines but I'm sort of worried of what I will actually be able to do.
I might just switch to chemE and take an extra year. Probably to much of a brainlet to make a significant contribution in research

>>8437204
>what are enzymes

>>8446282
>>8446291
Yeah, even with modern methods primary amination can be difficult. The Gabriel Reaction is one of those old reactions that nobody wants to use wholesale because of atom economy, but at the end of the day is widely used because it usually works (which is what matters at the end of the day).

>>8444981
That in the picture doesnt really count though, because once all the LDA is used up (after the first step only 0.2 equivalents LDA are left), there is no sufficiently strong base to turn the compound into an enolate. And since unlike the other compound, this isn't a vinylogic acid, you can forget about deprotonation by weak acids like the sulfinate generated by the reaction with trisylN3 or the diisopropylamine generated in step 1

>>8447942
woops *by weak bases

>>8447419
You do know that injecting testosterone will cause your body to produce more estrogen in response and you will grow tits and your nutsack will shrivel, right?

>>8447419
>are these guys even close?
lol, no. DHEA is a good starting material but the rest is bullshit.
>NaBH4
insufficient stereoselectivity
>MnO2
>selectively only oxidize only the 3-OH group
they think DHEA is an allylic alcohol, lel
>using technical grade products without purifying them
>inject
enjoy your necrosis
Also yeah there are many ways to make testosterone from DHEA, or cortisone or cortisol or progesterone etc... but if you only "have a basic understanding of chemistry" (=dont know jack) and dont have any lab equipment, dont bother.

>>8447942

What doesn't count? What are you talking about? The whole point of that picture is to prove that you can obtain an alpha-azido acid or ester without it spontaneously losing nitrogen as drawn in >>8444773

>>8446239

I was able to do some literature searching today and found that there is plenty of decent precedent for Darzens with ethyl bromoacetate.

>>8448031
Thanks. I suspected as much.

>>8448003
>injecting testosterone will cause your body to produce more estrogen in response
This only happens when your injection schedule causes high peaks and troughs. Injecting more frequently resolves this, as long as the dose is not excessive. I have been doing this for two years with no problems with E2 (estrogen).

> your nutsack will shrivel

This does happen but that a slow rate. Could not care less. Associated is a loss of fertility, usually but not always permanent. Again I don't care and indeed I have had a vasectomy.

>>8448256
>usually but not always permanent
permanent => temporary

>>8448031
>>inject
>enjoy your necrosis
injecting does not in itself cause necrosis. I assume you are suggesting that the impurities will cause problems.

>>8448031
>dont know jack
OK

What would I need to study to get up to speed? I am quite prepared to work hard for a long period of time. As an example I taught myself physics to graduate level.

Lab equipment is not a problem. I nave plenty of money.

>>8448269
>I taught myself physics to graduate level.
having previously done a pure math and statistics degree at honors level.

>>8448117
What loses nitrogen in >>8444773 is not the ester itself, but the enolate formed. I was pointing out why in >>8444981 no enolate or only small amounts of enolate could be formed from the azido ester. And i was actually overlooking the fact that the azide group on the molecule is only formed AFTER acetic acid is added. So the azido acid ester is actually formed in an acidic environment, none of it will be deprotonated. That of course doesn't mean that >>8444773 will really happen (can't say i know) but >>8444981 can't really be compared to it.
>>8448160
This is interesting, thanks. So >>8444334 generally looks like a good way to do it to me.

>>8447504
i always ask myself what went wrong in peoples childhood that makes them want to research fucking computational chemistry.
Had to do 3 classes and 1 project... Gets more boring the more you read about it. There is absolutely zero insight besides "i need more computational power than i ever could afford" to come up with real deal.. Too poor too afford enough computers? Lets take 400 grad-students that "optimize" our retarded models and make them come up with another stupid way to parametrize the 283462934692134619236 solvent molecules in your system so you can safe a bit of processing time....

...which in the end yields nothing since your algorithm fucked up after 3 days of calculating for reason you will never know.. Trying to reproduce your errors or anything? GOOD LUCK PAL - it's better to simply throw everything away you have and start all over again..
god i hate computational chemistry

>>8447383
I'm in the same boat as you ano. Finishing undergrad this spring. I had planned on phd but have been told by a number of my TAs that their degree really isn't all that valuable and to get an mba or law degree afterward. I enjoy chemistry but not enough to be stuck as a post doc for years making 15 bucks an hour

Probably going to graduate and go back to school for software desu and continue chemistry as a hobby

>>8448515
>t. brainlet

>>8447942
>once all the LDA is used up (after the first step only 0.2 equivalents LDA are left), there is no sufficiently strong base to turn the compound into an enolate.
What.
1st eq deprotonates the alcohol
2nd eq forms the enolate
Alkoxides are often fine themselves for generating ester enolates, but that's more appropriate under thermodynamic conditions

>>8448396
>the azide group on the molecule is only formed AFTER acetic acid is added
It looks like a straightforward quench, mate. Why do you think it says "30 sec"?


EXERCISE: Propose a diagram of 6 complexed with HMPA and LDA to rationalize the stereoselectivity of 6->7 in >>8444981

This probably gets asked a lot but whatever. What course has the most inorganic chemistry? Organic just isn't as interesting desu

>>8448543
>2nd eq forms the enolate
My bad, i phrased that ambiguosly. Of course an enolate is formed in step 1. What i meant is there is only 0.2 eq of LDA left to deprotonate the azido compound, forming an azido enolate. That is, if excess LDA isnt removed. Anyway, thats not important because of what i said here >>8448396
>why do you think it says "30 sec"?
Look at the pic again m8, it says 3 hours. 30 sec is for the reaction with trisylN3.
Heres a pic from Wikipedia to give you an idea. Different compound but basically the same reaction.

>>8448575
Why doesn't it provide stereoselection info, given that R' is a chiral auxiliary?

How does n-hexane extract β-carotene? I know it has something to do with polarity.

>>8449338
Water-soluble compounds: go into water.
Insoluble compounds: can be filtered away.
Hexane-soluble compounds: can be washed off the insoluble material and the solvent separated.

>>8449338
Mechanistically? Van der Waals forces.
You can go more in depth with this with computational models of solvation. One basic idea is that having a protic fragment (OH, say) or polar solvent "unmatched" via hydrogen bonding is less energetically favorable than when they match up, or are absent. This is why hexane doesn't dissolve very well in water, but is miscible with other medium alkanes. And, as it turns out, why ethanol is miscible with both water and hexane (in a mixture with both will partition between the two phases.)
Nonpolar compounds dissolve well in nonpolar solvents because the solvent molecules' intermolecular interactions aren't significantly stronger between each other than with the solute.

>>8449338
by not being polar
>i know it has something to do with polarity
is this just a shitpost?

>>8449338
>edvangelion

>>8449375
>>8449395
thanks
>>8449400
y-you too.

>Be pleb chemistry undergrad
>Deep in research, intermetallics type stuff, find it genuinely interesting
>Want to do something materials science related for grad school/career
>Shying away from biochem/orgo, partly because they aren't as interesting to me, partly because of job prospects

>Topic regularly brought up: "what do you want to do after graduation?"
>Fair number of fellow students say materials science

Should I still go for it, /sci/? Or is materials science doomed to become just another oversaturated discipline with too many degrees and not enough jobs for them to fill?

>>8449395
The "computational models" of solvation you've discussed aren't correct: solvation is always enthalpy versus entropy.

In order to solvate a molecule, the solvent molecules need to organize themselves around the solute. This comes with an enthalpic benefit (via non-covalent interactions such as hydrogen bonding, charge-dipole interactions, or dispersion forces) and an entropic penalty, as the configuration freedom of your solvent is now restricted to accommodate binding. Moreover, if you have to *break* favorable non-covalent interactions in the solute that comes with a penalty as well.

If the enthalpic term wins out, you get solvation. Otherwise not. Water/hexanes are a perfect example: because water has poorly stabilizing dispersive attraction to hexanes, the entropy term dominates and the two liquids aren't miscible. If you can't overcome the inherent non-covalency of the solute, you also won't get dissolution: salt won't go into hexanes because the dispersive attraction between hexane and the ions pales in comparison to the ionic attraction between the ions.

tl;dr, it's not just entropy

oops not just enthalpy

>>8449780
>Or is materials science doomed to become just another oversaturated discipline with too many degrees and not enough jobs for them to fill?

There were a lot of PhD positions at my university funded by Rolls Royce, I think, for jet engine design. Materials science is definitely a strong choice if you want to get a job rather than try to stay in academia.

>>8449883
Would you say chemistry is a good choice for an undergrad degree to go this route or would chemical engineering be better?

>>8449894

Well anon, if you want to be a materials scientist, I think you might do well to study materials science at undergrad level.

As far as I know, chem eng will teach you about fluid dynamics and how to design reactors and process plants. Chemistry at undergrad does not have a huge crossover with materials science, of course, I don't know what the structure of your course is, but chemistry won't teach you about metallurgy, for example.

>>8448269
Looking at the MIT OCW courses it looks like I would need to work through

Separation Process (10.32)
Thermodynamics and Kinetics (10.213)
Chemical and Biological Reaction Engineering (10.37)
Organic Chemistry I (5.12) and II (5.13)
Introduction to Organic Synthesis Lab (5.37)
Maybe Advanced Organic Chemistry (5.43)
Maybe Synthetic Organic Chemistry II (5.512)

Does this sound right? Or not?

>>8449998
This to work out how to make testosterone propionate and cypionate.

>>8447504
I hit it with HCL and protinate that lonely oxygen

>>8449998
holy shit, just go get some cialis or viagra or something if you want your dick hard or go find some exotic aphrodisiac

>>8450114
Your post falsely assumes that ED is the issue here. There are far wider implications of low testosterone e.g. osteoporosis, muscle wasting, depression etc.

>>8449998
That's overkill for what you're asking. You don't need theory, just find a reputable procedure and get a basic familiarity with lab technique. Zubrick's lab survival manual should give you a lot of mileage.

Ester formation, for one, is pretty general. I think Vogel's has a procedure using anhydrides, but honestly you can just look up the morphine acetylation procedure I'm sure erowid has and do something similar.

Remember to purify and characterize your product before you inject anything.

>>8450142
Thank you.

>>8449929
Thanks m8.

>>8450110
Fuck off

>>8450142
>Remember to purify and characterize your product before you inject anything.

What are you, some kind of sissy? Testing the compound on yourself is how you verify its purity/potency.

Hey guys, nice chemistry thread you got going on here. Do you know where can I find spectral (NMR, IR, etc.) data of more "exotic" compounds like Ferrocene or other organometallics? I know how to find crystal data using Pearson and International Cristallography Tables but so far, spectral data have been under my radar. Any help appreciated!
Picture obviously unrelated.

>>8451602
>8451602

It will be reported in the literature.

The 1H NMR spectrum of ferrocene will however be far too complicated to understand or rationalise with conventional techniques.

>>8451602
>Ferrocene
like, one triplet?

>>8451821

>triplet

>>8451602
Reaxys

>>8450110
xdDdd

>>8451696
>The 1H NMR spectrum of ferrocene will however be far too complicated to understand or rationalise with conventional techniques.
>>8451602

>>8438890
Assume you mean Cu(II)

Due to the Jahn Teller effect, caused by the d9 system having uneven orbital filling

non-sci here. have no idea what youre talking about. looks like a bunch of chem-dickwaving. how many years of college till i understand what the fuck im reading?

>>8452747
Not that much compared to other sciences. 2 years

>>8452755
>>8452747
definitely not true. if youre an undergrad chem, you'll understand some basic concepts, but to have colloquial knowledge on the chemical research climate and understanding of some of these syntheses not even most grad students can understand off the dome without googling

>>8444607
Nah, in Europe we deal with denatured ethanol in stead. Isopropyl you have to order online or something.

>>8451602
Look it up in Reaxys or use ChemDraw to calculate it

>>8453392
>eurocucks use denatured ethanol topically, in place of IPA
Christ, that actually explains a lot

>>8453392
>Isopropyl you have to order online
Who's stopping you from purchasing online? I know you only want exactly a liter, but have a slight excess is not bad.

>>8453392
Why?

>>8442469
>tfw taking organic and inorganic chemistry at the same time

>>8454887
Oof. It might not be so bad if the inorganic is more on the physical side (ligand theory, group theory, etc.) but it might be hard to understand the actual reaction mechanisms if you get that far.

How can I buy some Plutonium?

>>8453560
im german, desinfectant from the supermarket usually contains both ethanol and isopropanol. the denaturated >90% ethanol is to light your grill and for cleaning.

Anyone here an actual organic chemist or just highschool babies

>>8455239
im in organic chemistry 1 so im pretty much an expert

Very basic, but I don't really know where to begin with this:

2mL liquid-1-bromobutane is sealed in a 1L flask. We're given the desnity and vapour pressure of the compound (1.275 g/cm^-3 and 41mmHg) and asked whether any liquid will remain after the system reaches equilibrium.

Thanks in advance.

>>8455533
depends on local pressure of the vessel

>>8455536
That isn't given, this is first year so it'll be a simplification.

>tfw computational chemistry

>other chemists don't recognize me as one of them
>physicists think what I do is too imprecise to be interested in it
> computer science people don't understand the motivation

can't relate to anybody!!!

>>8455578
Are you in grad school?

>>8455638

Yes

>>8455578
How do biologists and bioinformaticians feel about you?

Science is math..

To calculate a chemistry expression/Problem, you're going to need to do math. Just to find the amount of Potential energy in an object is math. (And that is like 7th grade shit)

>>8455676

No idea, I've never talked to anyone in those fields except undergrads.

>>8455673
Ho do you like it? I was thinking of doing Something like that for grad school. How much wet lab work do you do? Do you think there's lots of opportunities after grad school?
Sorry for all the questions

>>8455771

I'm kind of new, I've only been in my lab like 20 weeks or so (in a fiveyear program, but we join a lab at the beginning of year 2). I actually barely do anything, I TA about five hours a week and for the last couple of weeks I've only had about 2.5-3 hours of stuff to do per day in the lab (as in, writing code for our lab's project) so I spend the rest of my time doing these things:

About 10% A: reading papers
10% B: learning new coding/quantum chemistry things from textbooks and online
80% C: doing nothing and freaking out about how much nothing I'm doing

Professor doesn't seem to care, which is good (nobody yells at me) and bad (not much guidance).

No idea about careers.

I do zero wet lab work except for when I TA freshman chem lab 101. Prof's lab is all computers.

>>8455680
Bacon: "Mathematics is the gate and key to the sciences."
Describing the world and making predictions in mathematical terms has several practical advantages over more heuristic approaches. But science isn't reducible to math

>>8455578
>>8455786
How bout you answer >>8447504

>>8455180
>the denaturated >90% ethanol is to light your grill
>denatured ethanol to light your grill

>>8455786
jesus just how helpless are you?

>>8455680
Mathematics is the queen of sciences.

>>8455536

It's obviously going to be atmospheric pressure you tool

>>8455836
Y'know, since you have nothing better to do

>>8455786
Thanks for the response

>>8437192
>tfw you still have a quarry to settle even tho you quit Dota a year ago

Anyone in medical/pharmaceutical chemistry around?
Pharmacy pleb here; wondering whether this is worth getting a graduate degree in, or if I should just switch to chemistry proper.
I don't feel like there's any use for a half-baked chemist/biologist/physician hybrid.

>>8456858
come back

>>8456972
>I don't feel like there's any use for a half-baked chemist/biologist/physician hybrid.
There is

>>8457149
Yeah, my physical chemistry prof is always complaining that the industry is snatching pharmacists before they even finishing their doctorate. But I always figured that in science, you should strive to do one thing well, which is already hard enough as it is.

Journal club time!
Read and discuss this seminal paper by Fukui, you degenerate HOMOs
https://scihub22266oqcxt.onion.link/10.1021/ar50038a003

Buckminsterfullerene ?

YOU GET COPPER CHLOROPHYLL - Chlorophyllin

YOU GET COPPER CHLOROPHYLL - Chlorophyllin

>>8458495

No, get out

>>8458246
just finished my POC class, hopefully I passed

I always used aromatic transition (WW/HF) state theory to explain my selectivities. If I read this paper before I might have used Fukui's method, but luckily for the course I only needed to know one method to determine the outcome of these types of reactions. FMOT is a lot more expansive but ATST works for me, except that finding the right descriptor for some sigma systems is pretty difficult

Can anyone explain me this part of Schöllkopf method
using (H3C)3-C-0 (-) BF4(+) in Et-O-Et

lol

>>8459775
Fuck it took me a while but you listed the wrong reagents lad

Its Me3O(+) BF4(-)

Has anyone ever considered manufacturing any illicit substances (MDMA, LSD etc.)?

>>8460205

No anon, that's illegal.

>>8460205
Yes, but the risks are too great.
If I were to get caught I'd lose my job, freedom, possibly wife.
But with the average price of MDMA being around 50€ per g (from what I remember when in college) - it's pretty tempting.
Plus I imagine living with the fact that you're making a substance that can kill/ruin other people's lives could be pretty disheartening.

>>8459775
>(H3C)3-C-0 (-)
wat
and what exactly are you asking for, the mechanism?

>>8455895
Let me ask what are the jesters of Sciences?

>>8460242
Not him but there's people who work for companies that are pretty much Satan.

>>8460242
>making a substance that can kill/ruin other people's lives could be pretty disheartening
Wow if you don't have the stomach to work in pharma then get in a fucking breadline
It all comes down to responsible use. If you don't bother yourself with the vaguest idea what you're getting into and how to be safe, you deserve whatever you do to yourself. Why require doctors and prescriptions in the first place? Jewish conspiracy?
You think the industry doesn't realize how many prescriptions are diverted for illegitimate use?

I used to retail RC benzos at school, the most trying part was this pale creep who'd bang on my door at 2 AM in the throes of withdrawal. I almost wanted to cut him off for a better night's sleep, but that would've been both a security risk and itself inhumane.

>>8460242
The risk is a big problem, but with any tryptamine or phenethylamine class drug i believe the benefits it can offer in therapeutic settings outweigh any ethical dilemmas, that said all drugs are in essence are like power-tools if used incorrectly can cause alot of damage. Its hard to draw the line for what ethical pharmaceutical practice should be, but the current model of highest bidder wins is pretty much as bad as pushing heroin in my opinion.

>>8460781

Except there's no guidelines developed for how to actually use those drugs to achieve some therapeutic purpose. Which might be due to lack of research, or maybe they're not as useful as they're cracked up to be.

>>8460790
well any kind psychedelics by nature is somewhat atypical, you can't exactly map the change in consciousness each person has in reaction to them, not in the way of x mgs had this biological affect. I think the best guideline you would have is treat it as any other psychotherapy session in a calm environment starting with a very small dose and gradually working up to higher doses. They shouldn't be treated as a consistently used medication you prescribe but as a tool to be used in addition to counseling and on an individual basis. But check out some of the work from MAPS and i believe some work is being done with lsd like this in i want to say norway.

>>8460833
>you can't exactly map the change in consciousness each person has in reaction to them
I think he was trying to gently help you realize you don't have the evidence to support >>8460781
>the benefits it can offer in therapeutic settings

The barriers to meaningful research with serotonergics should be lifted - because research is a matter of public interest and not because we have any promising data on clinical safety and efficacy.

>but the current model of highest bidder wins is pretty much as bad as pushing heroin in my opinion.
I find this funny, though. Who is it who's always the first to shit the bed when we talk deregulation?

>>8460866
well what model do you use to suggest therapy "works" to any measurable degree? Personal experience with them, and with others who have used them makes me feel they have a useful place in therapy, and yes this is opinion, how could it not be.

> the barriers ect.
this is true
>I find this funny ect.
sorry if i pushed to much there but if there is any shining example of what not to do in a pharmacological setting and a clear ethical negligence its with how large companies proliferate and "push" opiod and amphetamine based products with absolutely no regard to its sociological impact. Not all drugs are the same, and i'm not for a complete deregulation of all drugs, just the ones that make no sense to be regulated at all.

>>8460893
>well what model do you use to suggest therapy "works" to any measurable degree?
Well-controlled experiment.
It may be the case that you and others are misperceiving a benefit, it may be those of you who benefit from them are a strict subset of the general population and distinct in a psychologically/biochemically significant way which could impact potential as a treatment, etc. You always want an eye on the -nature- and -scope- of a method to properly understand it, and should seek these in objective terms.

>a clear ethical negligence its with how large companies proliferate and "push" opiod and amphetamine based products with absolutely no regard to its sociological impact.
I don't agree with this. There would be more precedent for holding liquor and car manufacturers, who do not treat medical conditions, responsible for the social impacts of drunk driving. And even that's a bridge too far for most people.
I think you misunderstood me. Only large companies can afford to get regulatory approval and bring a new drug to market, because the process usually costs 1.2 to 1.8 billion dollars and may take over 10 years. This is because the regulation is very strict.
It's the same people who are suspicious of the market being dominated by a few large firms who oppose any attempt to decrease the regulations that cause it in the first place

>>8460924
>well controlled experiment
I completely agree, i do believe there is a good amount of credible research in this, but sadly the bulk of it stopped after it was criminalized. I'd like to see more experiments that incorporate genetic disposition, or just in general a better objective bridge between what happens psychologically vs the biological mechanism in play.

>liquor & car manufacturers
well for the most part i agree with this, but there is a cultural recognition and community associated with alcohol, which i think is important, a bartender can cut you off if he thinks your taking it too far. But if you give someone a prescription of oxycotin and say okay this is for pain, it really doesn't give it the proper respect that drugs like that need. I agree that the cost for producing drugs/bureaucracy is too expensive but the profit needs to be a secondary motive, because after that large cost to bring a drug to market it also becomes the motive for why drug companies will push them so hard or try to bring a focus on drugs that are in essence guaranteed to bring profits, because they are addictive or necessary. Regulations are important but they only follow the idea of good practice, which medical companies in large part define.

I'm into molecular modelling/comp chem and want to pick up Python cos the software package I use most often has Python integration.

I haven't done any programming in about 10 years, so I only have at my disposal an understanding of how to construct arguments, but no knowledge of syntax or operator functions.

Can anyone recommend resources?

>>8460971
>it really doesn't give it the proper respect that drugs like that need
The pharmacist will counsel you on its use. Your doctor will also counsel you on its use before writing the script.
If you want to abuse it, that's your business. You can't get another script if you get addicted, you have to go to a methadone clinic for individual doses, get suboxone, kava/poppy seeds, or just ride it out. Doctors won't even give you extra to "taper off" when your pain management use is over, and even if you didn't abuse any along the way.
>push them so hard
>because they are addictive or necessary
Fuck, don't you just hate it when companies produce necessary drugs?
A large part of what you're railing against exists only in your head. Doctors won't prescribe something without a legitimate medical reason, to feed an addiction, etc.
I don't see what's wrong with marketing medicine if you can market coca-cola. Nobody's "pushing" anything on anyone.

>>8437176
A plane moves forward 5000 meters and upwards 2meters. How long will it have flown before it reaches its starting point?

>>8461004
I only have a soft-spot for it because i've had multiple family members and friends either go through addiction or die because of opiods and saying doctors do a proper job about warning their patients, or that the companies who produce them do, or saying that after a prescription runs out the legitimate use of pain pills will stop at the prescription and won't just slowly degrade into heroin abuse because its cheaper, or that methadone clinics do anything fucking more than put a band-aid on it and just cycle them through doses until they either get back on it or just nurse the wound for ten years. No, its a fucking problem, and when companies charge huge amounts for necessary drugs or companies like purdue try to market it like theres no issue or risk its sickening and they should know better. When you've had to pull a half dead girl off a toilet because she overdosed and try to wake her up, or jam a nalaxone needle into someones arm because the ambulance isn't there then you might have a fucking opinion that matters.

I have a biochem exam tomorrow but I feel like all the different enzymes, products are way too much to remember. The last biochem I did we could bring in a reference sheet with diagrams of the products and enzymes involved in various metabolic pathways.

Just seems ridiculous to remember off my head. Can any of you relate?

Am I on the right board? I'm looking for /sci/, the one with the people that normally just ask stupid questions and don't know shit.

>>8461054
Correct board, wrong thread. Here you go
>>8454755

>>8461034
>welp I'm out of prescription oxies better go shoot up some black tar now
>huh seems we have a family history of addiction, I'll just ignore that and go right ahead and get my own opiates though
>your opinion doesn't matter because I've had traumatic personal experiences
I've done heroin and U-47700 and had to administer naloxone too, I just wasn't a whiny bitch cunt about it. You're clearly looking for someone to blame.

>I've done this and that
>Your family couldn't handle
>whiny bitch

Piss off junkie

>>8459775
Draw a resonance structure of the amide to determine which site is going to be most nucleophilic.

>>8437630
Look at all of the complete idiots who think that Yttrium is a transition metal. Next thing you know they'll be saying copper is a transition metal.

>>8461371
ikr! clearly both are noble gases!

Speaking of transition metals, do you fags consider mercury to be a transition metal?

>>8461111
yeah, then you should know its not the fucking same as advertising god-damned coca-cola
>hurrr personal responsibility
well thats fucking great, good for you, because addicts always make reasonable decisions, and doctors always know whats best, and people always know what their getting into.
>i've done heroin
just make sure the next time you do it, you di enough to kill yourself, because i am looking for someone to blame for all the deaths and grief and your one of the assholes trying to say its not a problem.

>>8461371
>yttrium is a transition metal
>yttrium is not a lanthanide
>ytterbium is a lanthanide
>implying /sci/ can spell

Wow, this thread certainly went to shit.

GJ guys

>>8461749
>tfw chemistry threads always get derailed by loldrugs

I have zero chemistry knowledge and this is going to sound stupid but please answer it seriously.

Can you figure out which elements can merge together to form a molecule? Like for example H and O merge together to form H2O.
Do we know that because we've seen H2O or because there is a general formula/equation telling us H and O are "mergable"?
Is there a table somewhere with all possible molecules, or just a general system/equation which tells you if the molecule is possible/stable?

What about reactions? Do we know which elements merge together because we try it IRL, or is there a general formula which predics what will merge with what and how much energy is needed/released for it?

What about ppearance? Powder, gas, liquid, color, etc, can this be predicted, or do you have to make it and see what it is?

>>8461867
H2 + O2 __heat__> 2H2O

>>8461874
Fug 2O2*

>>8461874
I know. What about completely random elements? If i give you a set of 5 random elements taken from the periodic table, can you tell me which elements will merge/react together and what will the end result look like?

>>8461886
Give it a go and I'll tell you

>>8461893
Mt, Rb, Po, Sc, V

>>8461867
Yes this stuff can be predicted that's why the field of Chemistry exists. Take a class sometime, or a few.

>>8461867

Everything you've described is impossible and can only be determined using careful experimentation.

>>8461867
>I have zero chemistry knowledge
found your problem

>>8461924
>>8461934
Oh come on.

>>8461867
You can do maths, use group theory to predict if certain molecules are possible. Everything can be predicted using impossible for humans maths.

What are the best subdisciplines in chemistry and why?

>>8461934
bullshit. We can predict a lot of things, just cuz chemistry is stamp collection it doesn't mean other fields are.

>>8462019
orgo
its intuitive and useful

>>8461867
>>8461988
It's a very complex matter, so exact predictions are hard to make. But by simplyfing things a bit you can make pretty good estimations.

>can you figure out which elements can merge together to form a molecule?
Its better to ask which compounds would be stable. Start by considering basic things:
-If you only combine metal elements, you will usually just get an alloy. Otherwise:
-Would the compound be rather ionic or covalent? Consider electronegativities for this.
-If you got a simple ionic compond, consider the electrochemical potential of the ions.
-If you expect covalent bonds, try to draw a lewis strucure for the molecule you have in mind. If it's not possible without unpaired electrons, it's unlikely to be stable, but there are some exceptions.
-Compare the bond angles with the angles the individual atoms would prefer (use VSEPR because anything else is too complicated for beginners). If the bond angles are too violently bent, the molecule is unstable.

There are of course many more things to consider, such as mesomery, orbital geometry and overlap (especially hybridisation defects that may result) steric effects, etc. but you wont understand any of that right now. If youre interested, start reading about it, grab a school book for the start, Wikipedia may also be helpful. I've had a rather shitty chem teacher most of the time at high school and learned almost everything only by reading.

>>8461874
>>8461876

>4 oxygen atoms
>in 2 moles of water
>heat on the reactants side

Christ.

>>8461867
State of matter is determined by intermolecular attractions, they can be predicted by mathematics, but your average chemist should be able to make a reasonable guess at what's what when it comes to organic molecules based on what the molecule is made of.

Colour can be predicted based on trends observed in other compounds, this is especially true for transition metals.
For inorganic compounds, colours are usually the result of charge transfer between atoms (e.g. vapochromic Pt solids get their colour from the interactions between overlapping Pt atoms; their colour can be changed by altering the crystal structure, which changes the distance of the interaction).
Organic compounds commonly get their colours from their arrangement of conjugated double bonds. It's much harder to predict the colour of organic compounds without a computer to do some math for you.

>>8462019
Analytical is pretty cool because you get to use hi-tech stuff. Inorganic materials chemistry has some pretty funky stuff.

Of course you can specialise even further so there's way too many sub disciplines to list.

>>8462039
Useful, but it's dumbed down compared to other fields.

>>8462234
>dumbed down compared to other fields.
That's just the intro course, and that's just because premeds have to take it.

Hey chembros, I have a problem. I'm in third year of a 4 year Masters and it is becoming increasingly clear that my real interest is in quantum physics. Problem is, next year the best I can hope for is to join the physical and theoretical research group where hopefully I'll get to do some research in that area, but if I then want to do a PhD in say the United States, would I be able to join the physicists or will they reject me outright due to the 'Chemist' label?

I know this is off topic, but asking for advice here seems like a better bet than adv.

>>8444554
yeah, sure. they'll just give you some of their reagents for free. it's not like it costs money or anything

>>8462409
grass is always greener, isn't it?

>>8462409
Do you have a broad-based understanding of physics?

Anyone know the mechanism here?

>>8462409
I took your path, i'm actively contemplating killing myself right now. Make sure your interest is -actual- QM before you get into it, please.

>>8461867
>Can you figure out which elements can merge together to form a molecule? Like for example H and O merge together to form H2O.

That's a really good question. As far as I know, it's impossible to determine (at least in solid state chemistry) what the structure of a compound containing >2 elements will be.

>>8461942
>>8462024
Yeah, *some* things can be predicted, but to say *everything* can be predicted is rubbish. It's not impossible, but it's certainly not easy or general to do.

>>8462234
>dumbed down compared to other fields
Because it's not quantitative? Organic chemists typically need to be jacks of all trades to determine what's happening. You can find organic chemistry papers that span physical chemistry, biology, inorganic chemistry, green energy, and much much more. I wouldn't say they're smarter than the bunch, but it's certainly not an easy branch of chemistry.

would moving from molecular biology to biochemistry be a lateral move?

>>8463733

I'd draw some kind of concerted step with the aluminium pushing away a vinyl anion after getting gangbanged by all those water molecules, the carbanion can collect a proton on the way out.

>>8463733
>>8465219
Agreed. You'd generate a carbocation on the C-O carbon then react with H2O to form oxonium then deprotonate into the alcohol

>>8465372

What are you on about m8

There's no need to generate a carbocation, a water can attack the aluminium and push out the alcohol as an alkoxide. This is after the water has taken away the hydrides from the aluminium to form hydrogen gas.

>>8465372
>carbocation
>in an aluminum hydride reaction

>>8465188
Don't stop pipetting.
You're here until you die.

I have an oral exam coming up. Physical Chemistry. Statistical thermodynamics, quantum theory, spetroscopy, theoretical chemistry, kinetics and electrochemistry. I've been postponing this for a over a year now. Each day it becomes scarier in my mind. One more week left. I just wanna be done with this, i don't want to fail. I get so nervous in this exam situations, it's gonna be two profs, 45 min.
Tips?

>>8463733
Protonating the ever-living fuck out of everything bound to aluminum, that's what. Oxygen definitely protonates after you've formed H2 and protonated the carbon center. My guess is that you probably protonate at carbon prior to forming hydrogen, but that's not rooted in anything rigorous.

>>8466384
>Tips?
solve problems