The Periodic Table

orthocresol

12:05 AM

Happy New Year from Oxford, too!

2

getafix

6:52 AM

Happy New Year, from Nagoya too! (Well it is about 16.00 hours old, but who is counting).

a-cyclohexane-molecule

8:01 AM

Happy New Year from California :^)

3

mhchem

9:13 AM

This closed question chemistry.stackexchange.com/q/87628/24052 still gets upvotes on the answer. I cannot see who upvoted (regular users or newbies). I just wanted to bring this to an admin's attention. Maybe by not auto-deleting it, we can avoid some duplicate beginner questions in the future.

TanMath

Happy (slightly late) New Year from CA as well!

Loong

@mhchem This question has an accepted answer; thus, it will not be automatically deleted.

chemistry.stackexchange.com/help/roomba

Jan

11:14 AM

Almost happy 2nd of January everybody.

2

Loong

almost

Jan

It’s already arrived in the UTC+14 and other crap timezones xD

And I see that another attempt of mine at getting extra toppings failed, because the answer got stuck at +1. *sighs*

Loong

almost happy

Jan

Oh, I should have used brackets to avoid ambiguity. Almost ((Happy (2nd January)) everyone)!

Loong

I tried to use the site normally during this Winter Bash. And I actually have got the extra toppings on Chemistry.

Jan

11:22 AM

The thing is, I rarely have anything to add to already accepted answers …

And I have basically no idea how silentium is even possible on Chem.SE — even though users got it.

Loong

I have got Silencium on German Language.

Jan

It might be easier there.

But I don’t even find questions on chem.SE that haven’t been commented on D=

Loong

@Jan That is also a reason why Sportsmanship is difficult here.

Jan

But sportsmanship is inherently easier since there is no requirement for either answer to be accepted.

Loong

In a nutshell: 1 amu is defined to be 1/12th of the weight of C-12. What's missing is energy, $E=mc^2$. — Karl 2 hours ago

sigh :-(

This amu is really hard to kill.

4

Jan

11:31 AM

I would prefer to kill sulphur’s d orbitals first, though …

Time to collect the 2018 hat is running away Y__Y

Jan

11:49 AM

(Seriously, where are my sock puppets when I need them? Y__Y)

Loong

Hm, how can I search for questions with hand-drawn structures that could need replacement by proper ChemDraw images?

@Jan Which hat do you want now?

Jan

@Loong Ooooh, the star was so far back I didn’t see it O:)

Jan

12:02 PM

Here goes another attempt at the extra toppings o.o

orthocresol

12:52 PM

@Loong I haven’t done this actively for a long time (I usually just edit those on the front page), but I used to just go through highly voted organic-chemistry. Obviously a suboptimal solution. Let me know if you have a better way...

Loong

I tried searching for "enter image description here", but that doesn't work.

orthocresol

Googling that works

Loong

Ah

orthocresol

"enter image description here" "organic chemistry" site:chemistry.stackexchange.com gives me 4,170 results.

the top result is a -10 question.............................

Loong

site:https://chemistry.stackexchange.com/ "enter image description here"

about 9000 results

Abcd

12:58 PM

@Loong Hey! Could you tell me whether LG wade's organic chemistry is a good book or not?

Loong

I have no idea. Maybe @orthocresol ?

Jan

Before you guys suggest me: I can’t.

orthocresol

No idea, never used it before.

Maybe @Jan?

:)

Jan

@orthocresol :p

Abcd

Any organic chemistry book suggestions?

I already have Morrison Boyd.

orthocresol

1:01 PM

5

Q: Resources for learning Chemistry

Based on various other Stack exchange site (Mandarin Chinese, Russian and German), we adapt this project here for chemistry, since it's a great idea to have all kinds of resources in one place. This is a specifically created Community Wiki which gathers resources for learning Chemistry. The list...

Loong

1:13 PM

@orthocresol Searching for that is not so bad. Even if the found image is not a badly drawn structure, you can still try to replace the "enter image description here" with useful text.

orthocresol

Yeah, it's not bad. I didn't investigate but I imagine that a lot of them need touching up anyway.

Loong

@Jan xkcd 765?

I like homeopathetic.

Jan

!!xkcd/765

No clue what that is, sorry.

Loong

Dear editors of Homeopathy Monthly: I have two small corrections for your July issue. One, it's spelled "echinacea", and two, homeopathic medicines are no better than placebos and your entire magazine is a sham.

3

Jan

:D :D :D :D

Loong

1:23 PM

also the hover text

Jan

Nice hidden message!

And only 14 upvotes to go until I hit the rep hat.

Loong

2 hours ago, by Jan

(Seriously, where are my sock puppets when I need them? Y__Y)

But before anybody gets any strange ideas:

> Worry not! All normal site rules still apply. If you're caught sockpuppeting for hats, you will be suspended, just as you would be normally.

Jan

1:42 PM

> No, officer, I seriously have no idea why a number of porphyrins suddenly appeared to upvote answers I gave. No Sir, the number seven does not bear any special meaning to me; why would you ask?

orthocresol

2:14 PM

o.o I have 17 hats.

With the exception of Hero of Time none of them were intentional...

Loong

2:25 PM

also 17 after using the site normally, but I didn't try to get Hero of Time

orthocresol

I guess most of them are meant to be obtained through normal usage.

Jan

Hats I got by intentionally doing something I would not do normally:
– Too cool (but maybe now I’ll use the app more for casual browsing?)
– Hero of Time (but that was only delaying the time I was asking the question)
– Werewolf hunter (but if an old question shows up on the active tab and it needs an edit, I do so)
– Fascinator

Then there’s also I’ll handle this where I was actively looking for an opportunity to edit and reopen a question I had helped close after OP comments or something, and the comment deletion one where I went back and looked through old comments to see which were delete-worthy.

I may have biased myself towards actions that I would otherwise not necessarily have done otherwise.

As in I may have made sure to delete comments or post jokey ones that could earn upvotes.

Alan

2:44 PM

o/

Jan

Hi Alan o/

Alan

:-D

Hallo :-)

@Jan san lend me your powers!

yesterday, by Alan

I'f you aren't busy XD

yesterday, by Alan

^ Pardon the crappy handwriting O:)

< Gingerly pulls out 220 yen >

Jan

@Alan ༼ つ ◕_◕ ༽つ Sending Powers ༼ つ ◕_◕ ༽つ

Alan

< Falls to knees >

< Pulls out figurine >

Jan

3:01 PM

Something something radical. But … I’m unsure myself.

Alan

< Hangs head dejectedly >

Radical?

Why so? O:)

Jan

Maybe a radical grabs a proton from the methyl group; that then takes one electron from the C–O bond to open the epoxide and give an O-centred radical?

Alan

< Reads >

Jan

Then that could grab a hydrogen radical and potentially add HBr afterwards.

Radical because peroxides and light usually give radicals.

Alan

@Jan Ah, you're talking about the second half? :O

I suppose the first bit's O.K then? O:)

Jan

3:04 PM

Well, creating a Grignard reagent is also a radical reaction to the best of my knowledge but it is also what I would have guessed xD

Alan

< Bows in reverence to thy knowledge >

<- Still thinking about it

Loong

I guess already the first step would create all kinds of side reactions.

Alan

@Loong You're referring to the Grignard reagent attacking the epoxide?

Loong

For example

Alan

@Jan Ah sorry; now I'm not sure which radical you're talking about (oxygen?)

< Not very familiar with free-radical mechanisms (we only see halogenations at school) :/ >

Jan

3:09 PM

All sorts of radicals.

Alan

>_<

Jan

Also, I still haven’t finished my Christmas sake, and I’m contemplating going to 7eleven to grab a bite to eat.

Alan

@Jan This is quickly spiraling out of the scope of my textbook XD

< Hands @Jan 220 yen >

Jan

220 yen … I guess that pays for two onigiri?

Alan

Dunno? O:)

<- Blissfully ignorant of Japanese cuisine

Well, I'll be off for a bit. @Jan @Loong Thanks for today! :-)

orthocresol

3:23 PM

It would probably beta-eliminate and open the epoxide.

Well, not IRL, but for this question at least

Goodness knows what it does in real life.

Jan

So you’re suggesting that what I took as a hint to answer on this page is wrong?

orthocresol

Oh, I didn't look at that, so I didn't assume A was an epoxide.

Jan

I was thinking that epoxide opening may happen but then I saw that and discarded the idea ^^'

orthocresol

Well I have some epichlorohydrin lying around in the lab, we can test it out....

5 hours later

I got a black tar.

Loong

pubs.acs.org/doi/abs/10.1021/…

allyl alcohol is right

orthocresol

3:33 PM

o.o I didn't find that on Reaxys

Jan

@orthocresol Stop being so undergrad ;)

orthocresol

Technically no longer undergrad :)

Jan

You want me to call you ‘the student’ instead? ;)

orthocresol

Well I got a black tar once this year. Was probably some kind of polymerisation.

That one had to be chucked, unfortunately...

academic year, not calendar year

Jan

Oh, I’m not saying black tar in and by itself is an indication of the bad student, just coming back after five hours with only black tar and no answer is xD

orthocresol

3:38 PM

I see :D

Alan

@Jan Not sure how much of a "hint" that was (I could be terribly wrong about it) O:)

@orthocresol This looks promising :-D

Jan

@Alan Was it presented to you or did you come up with it yourself?

Alan

< Beams around with pride >

orthocresol

flags as NAA

Alan

:-(

NAA?

@orthocresol I'm curious, what software did you use to create that? :O

orthocresol

3:41 PM

ChemDraw

Alan

Ah, heard of it (not free, I believe) >_<

Jan

Not free, no. Also not available for good operating systems.

(And unfortunately the version for not-quite-as-bad operating systems seems to have several issues.)

*sighs* One upvote away from extra toppings Y__Y

orthocresol

downvotes

Alan

@Jan Where do you need it? ;-)

Loong

@orthocresol not allyl alcohol?

orthocresol

3:44 PM

hmph

Jan

xD

@Alan No, I’m not actually answering that because I don’t want to encourage you to upvote just because it was my answer or because I asked for it.

orthocresol

@Jan Not Actually Answering

Jan

@orthocresol NAA

Alan

3

A: Is it possible to neutralize acids with vinegar (e.g. when experiencing heartburn)?

This is bordering on a question asking for medical advice but at least the implicit claim should not be left undisputed. Neutralising acids with acids is something that only makes sense in the context of homeopathy — which I prefer to call homeopathetic methods to better underline their scientifi...

XD XD

orthocresol

The Batman Theme Song

►

Alan

3:47 PM

Oops

3

A: Reactivity of benzyl halides towards nucleophilic substitution

As you already noted, phenyl bromide is least reactive towards nucleophilic substitution, so any answer suggestion that does not place III last is wrong a priori. The reasoning you gave does not quite add up with me so here is my version: no $\mathrm{S_N2}$ back attack is possible through the phe...

XD XD

Pretty sure that's the one

Jan

I’m not saying anything without my lawyer’s approval any more o.o'

Alan

< Grins evilly >

Looks like you've got your hat ;-)

My job here is done :3

< dusts hands >

Jan

One of these days I will be accused of sockpuppeting seriously, I believe o.o'

Alan

O:)

yesterday, by Loong

@Loong You said that'd happen with an ester... will it also happen for an acyl chloride?

Jan

Less so, because a chlorine’s p orbitals don’t overlap well with the double bond.

Alan

4:00 PM

"Less so" I see! :-D

@Jan Would that make the carbonyl carbon of an acid chloride less electrophilic than the carbonyl carbon of a simple ketone?

I understand that an ester's carbonyl carbon will be less electrophilic (thanks to Loong)

Jan

@Alan Well, it’s typically more reactive. Not sure if that is because the chlorine is a leaving group, too (as opposed to an alkyl group).

Alan

But I'm wondering about acid chlorides..

@Jan :O :O That makes sense! I suppose that logic holds (doubly so) in case of simple carboxylic acids too?

^ (a proton leaves)

Jan

Well, no, hydroxide would be the leaving group. But also oxygen’s p orbital can interact well so there is a good deal of overlap reducing electrophilicity a priori.

Alan

< Thinks for a bit >

Jan

Now should I try to challenge andselisk for tied first place or am I too lazy? I think, the latter *yawns*

Alan

4:11 PM

Need to sleep? ;-)

Jan

That also. Meeting people in Kyoto at 11 tomorrow; that’s in ten hours …

Alan

<- Got a quick question before you leave (if that's okay with you)

Jan

Go ahead.

Alan

@Jan Between (simple) esters, acid chlorides and amides what would the order of electrophilicity (of their carbonyl carbons) be?

Jan

The order of reactivity is chloride > ester > amide.

Alan

4:16 PM

^^ (So I can think about it, and ask clarifications tomorrow...or whenever you're on)

@Jan Ah? Is that a standard thing (covered in textbooks)? :-)

Jan

Yes.

Alan

I see! Thanks :-)

And carboxylic acids don't count ^

As in: They "neutralize" Girg. reagents (right?)

Jan

Well, you didn’t include them :p

Alan

Um, heh? O:)

@Jan Because I'm told that Grig. reagents don't add across the carbonyl in that case O:)

Jan

> The order of reactivity is chloride > ester > amide > carboxylate.

Alan

4:19 PM

RCOOH + R'MgX -> RCOOMgX + R'H

Jan

I don’t know where exactly to put the free acid rn. I guess between chloride and ester though.

Alan

free acid? O:)

Jan

Free acid = RCOOH. Carboxylate = RCOO^-

Alan

Ah..

1 min ago, by Jan

> The order of reactivity is chloride > ester > amide > carboxylate.

You put that last ;-P

Jan

Yes, because the reactivity is different depending on whether the acid is protonated or not ;p

Alan

4:21 PM

< slaps forehead (in partial enlightenment) >

Jan

If you add ketones and aldehydes to the list, it is chloride > aldehyde > ketone > (maybe free acid here? >) ester > amide > carboxylate.

Right. Getting food now!

Alan

So if I've interpreted this right: Grig. reagents are much more likely to "neutralize" carboxylates than add across their carbonyls (and the opposite is true for chlorides)

See ya!

Thanks for today! :-D

Jan

4:46 PM

@Alan The first equivalent does. However, I would not be surprised if the second equivalent added to the carbonyl.

Alan

The first equivalent adds across the carbonyl?

< Grabs a pen >

I'm confused :3

Jan

No, the first equivalent will be neutralised by the acid.

Alan

Ah! I'm fine then :-)

(Psst, you don't owe me anything for those upvotes) ;-)

I liked those answers, so I upvoted O:)

Jan

Did you drop your pen like the German civil servant at 5 pm? xD

Alan

German civil servants hate work that bad (or is that a reference to the stereotypical German that's super-meticulous and finishes everything exactly on time?)

Jan

4:54 PM

It’s a common joke/stereotype on them being true to the letter of the law. So if the working hours are 9 to 5, they will stop working at exactly when the clock strikes five.

Alan

> I liked those answers, so I upvoted O:)

In other words, if you're tired or hungry, you're under no obligation to stay up and tell me useful stuff ;-)

Jan

(The fact that they are considered slow and unwilling to work out of their own motivation contributes)

I just got food and ate it. Now I have to finish sake.

Loong

@Jan You haven't seen a Finnish office then.

Jan

And once that sake is drunk, I can officially begin dry January.

Alan

@Jan Ah :-D

Jan

4:55 PM

@Loong Oh yes, I have. I guess, Germany and Finland are once again very similar xD

Alan

@Loong You're Finnish? (You gave off a German vibe though ;-P)

Jan

Eihän hän ole.

Loong

They come at 7, breakfast break, coffee break, lunch break, coffee break, leaving at 15:00, then sauna.

Alan

@Jan < Perfunctory nod; doesn't understand a thing >

Jan

Oh I know ;)

Alan

4:56 PM

:O

Jan

I mean, they don’t pretend they’re working; that makes it better xD

Loong

Yeah

Ismo Leikola - The Most Important Word In Finnish (English subtitles)

►

Jan

(I think, I have no need to finish the sake. Oh well.)

pentavalentcarbon

@Jan btw this is coming out in a few days: myanimelist.net/anime/34382/Citrus?q=citr

Jan

@pentavalentcarbon I saw at Comiket =3

pentavalentcarbon

5:06 PM

I have very low expectations tbh

Jan

Y?

pentavalentcarbon

The manga is 99% silly drama, 1% bait, and 0% action

Come on!

And shows are always censored compared to the manga

Jan

Shh, I liked the manga (up to where I read at least).

pentavalentcarbon

I mean, it's fine, and of course I'll watch it...

Jan

The animation studio and producers are unknown to me. But the director also directed Spice and Wolf. So it’ll be good ~ <3

Alan

5:17 PM

I think I waded into a conversation that I shouldn't have o_o

Jan

How come?

pentavalentcarbon

go back to chemistry and stuff I don't understand

I should put Spice and Wolf on my PTW...

Jan

Chemistry and stuff you don’t understand … a love pentagon? Love is chemistry, no?

pentavalentcarbon

Oh, it is in my PTW and plan to read already

So much to do, so little time...

Where'd you get love pentagon?

Jan

I think, Shuffle has one.

pentavalentcarbon

5:31 PM

Oh dear, this is a world I'm not familiar with...

Jan

5:56 PM

With that, I’m off o/

Loong

7:10 PM

sigh more snow

Geoff Hutchison

8:16 PM

BTW, I posted a possible molecular design challenge - feedback welcome before I post it next Monday.

1,3-feeds

9:15 PM

2

Q: Suggestions for molecular design golf problems

Synthesis golf started over summer, and there is clear interest in a non-synthetic molecular design golf to explore the diversity of molecules. This meta question is intended as a compilation of ideas for molecular design questions for future use. Each month, we'll use one of the targets (that ...

discussion

1

Q: Everything you need to know about molecular design golf

Contents What is "molecular design golf"? How is this different from "synthesis golf"? What should my answer include - are there any rules? What resources do I need to participate? What is the correct answer? What incentives are there for me to participate? What are some previous molecular desi...

discussion community-wiki

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