I see your channel isn't too big as of right now but keep on pushing these videos out please. These are really high quality and are helping me and many others learn o-chem and have been really fun to watch. I wish you the best going forward, I'm learning a ton with these and excited to take this in college very soon :)

@ThatChemistOld

2 жыл бұрын

Thank you - the channel is growing fast, and encouraging comments like yours are motivating me to keep it going!

I’m a PhD student in Organic Chemistry and I’m really addicted to your videos 👏🏼👏🏼👏🏼 congratulations

@ThatChemistOld

2 жыл бұрын

Glad to hear it :D

For the sulfonyl chloride synthesis there's a really handy reaction that uses thionyl chloride/CuCl as an in-situ sulfur dioxide source. Makes it a lot easier than handling SO2 gas + they actually use water so you don't need to worry about drying solvents (low solubility of the sulfonyl chlorides in water protects them from hydrolysis). DOI: 10.1021/op9000862

In grad-school I developed a prep for 9-hydroxytriptycene (to use as an alkoxide ligand for tantalum complexes, which could not undergo elimination) starting with benzene diazonium carboxylate (from anthranilic acid and isoamylnitrite) to generate benzyne, which diels-aldered in-situ with 9-anthrylacetate (from 9-anthrone with KH and AcCl) to give 9-triptycylacetate (33% after recrystallization) which was hydrolyzed with KOH/H2O/MeOH. This was the only diazonium reaction I ever ran. From 9-anthrone, with recrystallizations of the acetates and the final alcohol, the overall yield was about 21%.

@ThatChemistOld

2 жыл бұрын

I love triptycenes - they look like the Imperial Shuttle from Starwars

@robertlapointe4093

2 жыл бұрын

@@ThatChemistOld Yeah, the shape is neat and we thought it would be perfect for our use (making homogeneous transition metal complexes that would be analogous to metal oxide supported transition metal catalysts), since it was so sterically large, on paper at least. In a real tantalum complex though, two triptycyloxy ligands went axial (imagine two shuttles docked nose to nose), leaving three large missing-pie-slice spaces for three equatorial neopentyl groups. That compound was such a brick that even boiling it in aqueous HCl required days for hydrolysis (tantalum alkyls usually blow apart with just a whiff of atmospheric moisture). Our original candidate for fat alkoxide ligand, tri-tert-butyl methoxide, fell apart (to tri-tert-butyl carbonium and derivatives, a.k.a. tar) as soon as I put it on tantalum. While the triptycyloxy solved that elimination problem (non-planar carbonium ions are energetically unfavorable) the deceptive sterics killed it for its intended purpose. What finally did work (and lead to lots of interesting chemistry) was the tri-tert-butylsilanolate ligand. The silicon-oxygen bond strength shut down the elimination problem and the three tert-butyl groups provided very satisfactory bulk.

Great vid! I really appreciate these organic chem lessons and the practice problems that you give at the end. Keep up the good work.

@ThatChemistOld

2 жыл бұрын

Thank you!

The perchlorate salt of benzene diazonium was considered for use as an explosive by the Germans in WW2, but production was halted when a couple of large scale accidents proved the material too unstable for industrial production

@chemistryofquestionablequa6252

2 жыл бұрын

Were they going to use it as a primary?

@briang.valentine4311

2 жыл бұрын

@@chemistryofquestionablequa6252 It is a primary explosive, because it is so shock sensitive. They planned to fill shells with it. It is also terribly easy to make, unfortunately, and a lot of people have been seriously hurt with it

@chemistryofquestionablequa6252

2 жыл бұрын

@@briang.valentine4311 I thought it sounded like a primary. Not the best idea to make a whole lot of those. Also not great for filling shells. Of it's that sensitive it'll probably detonate on firing.

@briang.valentine4311

2 жыл бұрын

@@chemistryofquestionablequa6252 Either that or fill a bomb with it. They called it "Blitzkrieg powder." About the only good thing to come out of all of this was perfection of techniques to make ammonia from the elemental gases and rhodium catalyzed oxidation of it to nitrate. Despite a lot of industrial R&D the processes really haven't changed much.

Just got through O chem 2 and benzene chemistry was definitely my favorite unit! Nice video

@ThatChemistOld

2 жыл бұрын

Thanks!

I'm a recently graduated undergrad student and I watch your videos throughout the day and when I go to sleep. Thank you for the quality content. The Organic Chemistry Tutor was pretty helpful on one hand, but your videos give much more "real-world" application. Thank you and keep up the great work! Also, from a mechanism standpoint, why do most of the diazonium precursor reactions have HX, NaNO2, AND water? From a standpoint where you want to use the diazonium instead of an aryl halide: 1. I thought that the diazonium salt would turn to the aryl halide spontaneously (without possible isolation as described ~4:20) 2. Even if the diazonium was isolated, wouldn't the water wash turn it to a phenol (i.e. at 7:20 the thiolation would start with the phenol rather than the diazonium/aryl halide precursor)?

@ThatChemistOld

2 жыл бұрын

it depends on conditions - usually without a copper salt, it will require a bit of heat to decompose the diazonium in the case of the thiolation, they isolate the diazonium salt first - if you look at the Mayr N parameters of a xanthate, they are smoking good nucleophiles - among the best nucleophiles

+1 for the new bioisostere, arylsulfur pentafluorides. Their stability is quite astounding.

@ThatChemistOld

2 жыл бұрын

At least the aryl ones are stable from what I hear - once some better methodology for their synthesis have been demonstrated, I think we will be able to make a judgement call on alkyl-SF5 stability. I know the people working on the alkyne/alkene SF5Cl chemistry, but it is still in its infancy. The new hype motif is Ar-SF4-CF3 (cis and trans).

@donciterenyi4494

2 жыл бұрын

Trans Ar-SF4-Ar linkages are also quite interesting and stable enough with nitrogen heterocycles

@Dev-ih1of

2 жыл бұрын

Never in my life I expected to meet someone named Acetophenone

In the first nitrile substitution shouldn't copper 2 cyanide react to form cyanogen?

@ThatChemistOld

2 жыл бұрын

based on my brief glance at wikipedia, yes - so they must be using an excess of cyanide, sacrificing some of it as a reductant

Dear doctor,how we can monitor the progress of the diazodization reaction ?I think that TLC is not suitable as the diazo compound will be decomposed upon exposure to light and higher temperature during the withdrawal and putting spot and adding tlc into eluent?

@ThatChemistOld

2 жыл бұрын

you could still see if there is unreacted SM by TLC

@ahmedhegazy6080

2 жыл бұрын

@@ThatChemistOld sorry what SM stands for??

@vialb2

2 жыл бұрын

@@ahmedhegazy6080 starting material

1:07 wait, I thought that the mozingo reduction was supposed to reduce the thioacetalized carbon only, giving back the dithiol. Does the sulphur actually end up in H2S?

@ThatChemistOld

2 жыл бұрын

no the sulfur ends up as NiS

@ThatChemistOld

2 жыл бұрын

and propane

How does gatterman rxn work...is it same like sandmeyer?

@ThatChemistOld

2 жыл бұрын

it's an EAS reaction - protonated hydrogen cyanide engages a lewis acid catalyst, and is able to acylate arenes

I'm really awful and temp control and constantly fail the sandmeyer. Is there a minimum temp to form this salt or can I use dry ice and acetone to avoid overheating?

@ThatChemistOld

2 жыл бұрын

It is substrate dependant - if there is an organic syntheses procedure I would follow that - is the substitution step or the diazotization step the issue for you?

@bobsagely812

2 жыл бұрын

@@ThatChemistOld it's just iodobenzene, at first I had thought it was because my aniline is near brown but now I'm convinced it's just me being impatient and letting the temp rise too much lol. Usually I don't make it past the first step and I end up with a flask of sludge

@ThatChemistOld

2 жыл бұрын

@@bobsagely812 I've made 2-iodobenzoic acid from anthranilic acid and it was really easy - it might be easier for that particular example though

@ThatChemistOld

2 жыл бұрын

@@bobsagely812 if you follow this org synth, it should totally work - orgsyn.org/demo.aspx?prep=cv2p0351

@bobsagely812

2 жыл бұрын

@@ThatChemistOld yeah Strangely enough ibx is the only one I've had success with. Seems like Temps over 20c will kill the iodobenzene synthesis

mind if I pick your brain before your channel becomes too big that you don't have time for me? I want to make some organic soluble ionic liquids, more or less from scratch is minimal equipment as I can't afford precursors. I'm guessing I could start making phenol from my aspirin on the way to make the diatonium.... Some background, did some pretty crazy chemistry as a child, crazy for a child anyway, went to college with major in biochemistry but changed it to computer science, dropped out after spending all my money after bad breakup.. make most of my living as a house painter and now retired on social security.... doing some chemistry more as a hobby now.... I'm wondering why some of my ideas were never realized by somebody else in last 35 years. I'm not a mad bomber or drug lord, I've heard enough jokes with my long beard and weighing chemicals with my pinky nail..... currently I would like to build a cheaper big battery if just for myself.

@ThatChemistOld

2 жыл бұрын

I always will make time for interesting disscussions! the easiest ionic liquids that come to mind are imidazolium salts or quaternary ammonium salts (alliquat)

@petevenuti7355

2 жыл бұрын

@@ThatChemistOldyes(I had to look that up, you thought of that off the top of your head) My problem right now is a sub$100 budget and trying to do from household items.

@petevenuti7355

2 жыл бұрын

@@ThatChemistOld think denatonium would make a more easily sourced cation then diazonium? not sure how to get diazonium from a phenol anyway. ideally I'd want something more hydrophobic. is it even possible to have an ionic liquid that's immiscible in water? I'm guessing it be better to talk to you through discord then the comments?

@petevenuti7355

2 жыл бұрын

@@ThatChemistOld any chance there's a video in the works for preparation of imidazolium or quaternary ammonium compounds. Comparatively cheap precursors? Any interesting choices for anions? I'm guessing your a professor? And of course for my application, it's best to avoid the more hydrophilic compounds, be water insensitive or at least find a way to deal with it.