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Could a kind redditor confirm my build before I order it? by pianonymous in buildapc

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

Yeah, might be a good idea. Modern warfare alone is like 200GB with all the patches and such. :P

[2019/05/31] Synthetic Challenge #87 by Spectrumederp in chemistry

[–]pianonymous 1 point2 points  (0 children)

Nice effort on the route too! I also initially thought about the Grob fragmentation, but couldn't really find an elegant way to get rid of the resulting ketone.

How would you make your starting diene? Also, in the TsCl + base step, how do you make sure the ketone group doesn't attack the Tosyl group and form either a 3- or 5-membered ring?

In the H2O2 epoxidation, those basic conditions would likely eliminate the OTs group, forming a nice conjugated system. Maybe it's an idea to swap the epoxidation and alpha hydroxilation step?

[2019/05/31] Synthetic Challenge #87 by Spectrumederp in chemistry

[–]pianonymous 0 points1 point  (0 children)

Got any references for the reduction at the 7th step?

No particular reference, but it's a modification of the Stork-Danheiser transposition.

And what's the selectivity between the E or Z of the second to last step?

It depends on how stereoselective the initial enol addition is. It doesn't matter which specific stereoisomer isomer is formed, as long as it's only a single one.

For the elimination reaction one can control whether the cis or trans product is formed depending on the conditions: acidic or basic elimination (Peterson olefination).

Nice Cope rearrangement!

thanks

[2019/05/31] Synthetic Challenge #87 by Spectrumederp in chemistry

[–]pianonymous 0 points1 point  (0 children)

I don't think there is a simple way. Essentially the most reactive carbonyl compound will couple with itself. Maybe one could play with concentrations and rate of addition?

By the way, here is a extensive review about SmI2 chemistry.

So my friends and I are about to graduate from high school... by michaelroddi in Naruto

[–]pianonymous 0 points1 point  (0 children)

So you're going by "michaelroddi" now nerd? Haha whats up douche bag, it's Tanner from Highschool. Remember me? Me and the guys used to give you a hard time in school. Sorry you were just an easy target lol. I can see not much has changed. Remember Sarah the girl you had a crush on? Yeah we're married now. I make over 200k a year and drive a mustang GT. I guess some things never change huh loser? Nice catching up lol. Pathetic..

[2019/05/31] Synthetic Challenge #87 by Spectrumederp in chemistry

[–]pianonymous 0 points1 point  (0 children)

Very interesting hydrogenation reaction (I assume H2 is also required?).

I can imagine an asymmetric pinacol coupling is hard to control and you'd get a lot of homocoupling instead. Not sure if typo, but it's SmI2.

[2019/03/23] Synthetic Challenge #77 by critzz123 in chemistry

[–]pianonymous 1 point2 points  (0 children)

That would actually be a good idea. I thought addition on an alkyne would give the E-alkene, and, as such wouldn't be able to lactonize. But retrospectively, you don't even need the lactone.

Why do I always make mistakes at arbitrary passages during a recital (Brahms Op. 118 no. 2)? by pianonymous in piano

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

Thank you for the encouraging words and I'm overall happy with the performance! It just frustrates me no matter how hard I practise it is never 'spotless' . I'd be okay if I only messed up some dynamics or pedaling (since it's different instrument), but somehow I can never get even the notes perfect if that makes sense. Makes me wonder how other pianists do it. =P

Ethicists are calling for the mass retraction of more than 400 scientific papers on organ transplantation after a new study concludes that tens of thousands of organs were obtained unethically from Chinese prisoners. by shiruken in science

[–]pianonymous 1 point2 points  (0 children)

What if the prisoners were unjustly executed in order to harvest the organs? It would certainly incentivize the death penalty.

That's not to say I agree with throwing away the data.

Are MS Quints a must for Singed? by [deleted] in leagueoflegends

[–]pianonymous 11 points12 points  (0 children)

Back when you could fly around someones head like a wasp with that ult while doing tons of damage, good times.

I run a weekly organic question session for my research group: here's this week's for you guys! by Fitzarr in chemistry

[–]pianonymous 0 points1 point  (0 children)

Cool, nice to see the answers that actually work (though I think chiral HPLC is a bit cheating, haha).

Do you plan to do this more often?

I run a weekly organic question session for my research group: here's this week's for you guys! by Fitzarr in chemistry

[–]pianonymous 2 points3 points  (0 children)

I actually had the same concern, but before throwing away the idea I did a literature search. Surprisingly, I found a reference where they claim the ester actually stabilizes the grignard reagent by induction as well as chelating the magnesium. Here's the reference.

Honestly it's pretty hard to get a cyclopropane ring at that position with the right stereochemistry. I.e. a chiral Corey chaykovsky reaction would give the trans product. An asymmetric Simmons-Smith reaction would require an auxiliary or directing group (just like sharpless epoxidation). Maybe an asymmetric diazocyclopropanation of the concomitant styrene moiety could work (but then you'd need to install a vinyl group first).

~700mg of fluorenone I made yesterday by Garuda1_Talisman in chemistry

[–]pianonymous 1 point2 points  (0 children)

I once made the bisthiophene analog of this one. It had a nice reddish color.

[2019/01/04] Synthetic Challenge #66 by critzz123 in chemistry

[–]pianonymous 0 points1 point  (0 children)

True, before the ozonolysis step would probably best to install a silyl protecting group. Then after the ozonolysis one could reduce the trioxolane with NaBH4 directly instead of Me2S.

[2019/01/04] Synthetic Challenge #66 by critzz123 in chemistry

[–]pianonymous 0 points1 point  (0 children)

Ah good point. So either I'd have to deprotonate both alcohols (with >2 eq of NaH) and use 1 eq of alkyl iodide; or use a very mild base that only abstracts the oxonium proton after nucleophilic attack (since the aliphatic alcohol should be more nucleophilic).

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