Alyx Woodward (obsolete) @Alyx@computerfairi.es

methyls are tacked onto the unsubstituted vicinal amino groups by an odd procedure, but one I think that insures that the nitrogens get one methyl each. direct methylation of the nitrogens (e.g. with methyl iodide) would probably yield the tetramethylated product chiefly, or if you could stop the reaction at disubstitutions, you'd get one dimethylamino group and one unsubstituted one

instead, ethyl chloroformate is used to tack on carbethoxy groups, which are then reduced to methyl with LiAlH4

I'll just name a couple features of the synthesis

the chiral ligand being synthesized is a vicinal diamine, i.e. a derivative of ethylenediamine, H₂NCH₂CH₂NH₂. vicinal diamines tend to be excellent ligands for transition metals, such as nickel, here

the molecule is a symmetrical one! it's chiral in the same way that tartaric acid is chiral

there's some kinda odd Cope-type rearrangement in the first step that breaks a carbon-carbon bond and makes a new one, in a concerted fashion

here's the full title

Synthesis of Chiral Diamine Ligands for Nickel-catalyzed Asymmetric Cross-couplings of Alkylchloroboronate Esters with Alkylzincs: (1R,2R)-N,N'-Dimethyl-1,2-bis(2-methylphenyl)-1,2-diaminoethane

yeah. soak that one in

synthesis of an ingredient of a chiral catalyst meant to be used for one very specific coupling reaction between organoboron and organozinc reagents

like, I think about wanting to do this sort of chemistry every time I get out of bed in the morning

ok, _Organic Syntheses_ roulette time again

the word of the day is "distinct"

http://orgsyn.org/demo.aspx?prep=v96p0245

*winces* this is a very new one, and I've been hoping not to have to comment on it because it's sufficiently complicated to defy any easy explanation, and because the aim of the synthesis is so _specific_

I've complained before that O.S. methods used to be ones of great generality but I suppose they've run out of easy targets

Kel...wherever you are, I kinda hope you bump into Jupiter or Neptune on the way out, and you decide to stick round. like, not around US, but just...around

I miss you chasing electrons around molecular orbitals and shit

ok now I AM crying

where Kel really came from I don't suppose we'll ever know

all that seemed to point to one definite indication: whatever Kel's identity, there was a strong chance xe was just "passing through", as it were

and that's more or less how it seemed to work out. Kel's influence waxed and waned, and last night, Kara accepted that xe was outboard bound. Kel flew in, changed our lives, and is flying out again, leaving behind a plush version of xerself to keep us company

*looks down, refusing to cry*

starting I dunno how many months ago Kara sussed out that the _apparently_ draconic entity Kel the Purple, who'd been part of our system since early 2017, was (a) maybe not really a dragon and (b) seemed curiously to have associations with hyperbolae, and also with comets, which are one of the few observable celestial bodies found to travel in hyperbolic trajectories

also this procedure shows how to split open a phenyl ester with methyl iodide. but who wants to play with methyl iodide, yuck

such free-radical reactions tend to have, at best, "moderate" yields and to produce by-products because of the high reactivity of free-radical intermediates. but intramolecular substitution, as here, seems to improve yields considerably. looks like electron-withdrawing groups on the phenyl ring (e.g. nitro, trifluoromethyl) decrease the yield to roughly 50% or lower. still okay, honestly

peroxydisulfate (usually in conjunction with silver catalysis, sometimes copper or other metals) is a fascinating organic reagent that's of use in certain oxidation and free-radical reactions, in organic chemistry

for instance the "Elbs hydroxylation" uses persulfate for para-hydroxylation of phenols (e.g. phenol to hydroquinone)

there's some similarity here in that the species attacking the aromatic ring is an oxygen species, probably the -COO. radical

now for _Organic Syntheses_ roulette

first random word I'm trying..."dance"

wow that actually matched a few articles. the first match is one I've already hit recently (i was the oxazole synthesis using an amide of N-aminopyridine) so I'm rolling with the second one

http://orgsyn.org/demo.aspx?prep=v95p0097

an intriguing and rather simple reaction, intramolecular ring-closure of o-phenylbenzoic acid to 6H-benzo[c]chromen-6-one (the fundamental ring structure of "urolithins") using peroxydisulfate and AgNO3

(I feel inclined to twit Chara a bit about that one, seeing as how they work "determination" into conversation an average of three or four times a day)

🔴 I'm not THAT bad

yeah sure let's ask @KaylinEvergreen about that

trying to spot anything noteworthy in the _mise en scene_. one detail that stands out is that there's a big chart labelled "SPECTROSCOPY" on a wall, but it's taller than it's wide, which is not usually how visible-light spectra are shown on a chart. also it goes from pink to white to yellow, but I'll chalk that up to stylization (or simplification)

finally Prof. Rodgers offers the help of after-school tutoring to Lomax...if they have "some DETERMINATION"

dun dun DUN!

the conversation between Lomax and the teacher, Rodgers, continues

https://www.parallaxcomic.com/comic/page-08

still no definite answer about why Lomax is in classes they do badly at (do we know Lomax's gender at this point?) but they're hinting that parents aren't the reason. well, like I said last night, it's fair to assume there's some _exciting_ reason for Lomax forcing themselves through classes they suck at other than the obvious ones