Author Topic: p-benzo pics... no bees want to see? =(  (Read 4800 times)

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homeslice

  • Guest
p-benzo pics... no bees want to see? =(
« on: October 15, 2003, 07:38:00 PM »
Swim recently synthed some p-benzo from h2o2 and he asked me to post these photos for him. Other pics on the hive dont resemble this at all. But when described by text they match the description. These are after recrystalization and drying.










Swims just a little concerned about it because he spent hours reading p-benzo posts on the hive and has yet to see a picture that looks like this.  :(  So what do the bees think?

GC_MS

  • Guest
My commercially obtained pure 1,4-benzoquinone
« Reply #1 on: October 15, 2003, 08:22:00 PM »
My commercially obtained pure 1,4-benzoquinone is yellowish. I have purchased the same substance from SA and theirs turned out to be greenish (and contains an impurity; I don't know which one, but it was hard to remove it from certain reaction mixtures).


homeslice

  • Guest
so?
« Reply #2 on: October 15, 2003, 08:46:00 PM »
GC_MS: so whaddya think?  ;D

Vitus_Verdegast

  • Guest
quinhydrone?
« Reply #3 on: October 16, 2003, 02:11:00 AM »
That is probably quinhydrone, these are green crystals with a metallic shine.
Is it possible to oxidize hydroquinone to p-benzoquinone with just H2O2? Any ref you got for this? When I tried it it gave are really darkgreen, almost black solution of the charge-transfer-complex quinhydrone.

If you oxidise this further with a suitable oxidation agent, you'll get p-benzoquinone.

Quinhydrone may very well be the contaminant of commercial lightgreen benzoquinone.





ChemoSabe

  • Guest
Chem Porn Revival
« Reply #4 on: October 16, 2003, 02:53:00 AM »
Nice images. Sometimes such imagery is referred to around here as chem-porn and I hope you and other bees continue to produce and show more images such as this.

Much like sex oriented porn, seeing it sure beats the hell out of just reading about it.


homeslice

  • Guest
hmm
« Reply #5 on: October 16, 2003, 03:52:00 AM »
Chemosabe: Thanks. I wish the hive had a place to upload photos to. I think if it did in the future more bees would display their work maybe?

That was the exact reason why i posted pics to make sure they weren't quinhydrone. They are definately NOT black. The crystals DEFINATELY look like the color of gold. Id say it really resembles fools gold, since swim has seen quantity of this. The color is hard to see in these pics as they were taken with a cell fone  :)
Its not just h2o2 its 35% h2o2 that was ordered by swim from a chem supplier.

Some refs: The original synth is on Rhodiums site but its also reiterated in this post by overclock. Ive also seen overclocks version of this synth referred to in other posts.

Post 257969 (missing)

(overclock: "p-benzo via H2O2 etc ...", Newbee Forum)

Post 436933

(TheHobbit: "p-Benzoquinone via H2O2/I2 reaction", Chemistry Discourse)

Post 457743

(blaaky: "p-benzoquinone via h2o2 results", Newbee Forum)
     <-- now this is the post with one of the pictures that worried me into thinking that i fucked up.  But then i did the synth again and got the exact same results with about the exact same yield as prescribed via overclocks method.

Its tough as a newbee chemist to look at something you made and say that its the right stuff. Like i want to believe that that is 100% pure p-benzoquinone, but then i read on here posts that have conflicting ideas on what p-benzo should look like, smell like, what color it should turn when its placed on ur skin. And then reading conflicts like this makes me wonder if swims work is absolutely wrong because obviously these bees posting these conflicting reports have more exp. than swim.  :(
I got some reassurance in swims work though when I stumbled upon a post on the hive that was written by an experienced bee, I cant recall whom (shouldve bookmarked), that mentioned how newbees can look at safrole and see that it distilled at the right temp, it refracts like, it smells nice and pleasent and every other thing that safrole should be... and then STILL doubt their work. Like swims p-benzo seems to be bright yellow crystals that burn your eyes and nose just going near them but then it makes me wonder if swims just in disbelief because hes a newbee and doesnt have a shred of confidence.  :(  I dont know just my two cents buts its prolly more like newbee rambling to many.

Vitus_Verdegast

  • Guest
steam distill if you really want to be sure
« Reply #6 on: October 16, 2003, 04:55:00 AM »
That was the exact reason why i posted pics to make sure they weren't quinhydrone. They are definately NOT black. The crystals DEFINATELY look like the color of gold. Id say it really resembles fools gold, since swim has seen quantity of this. The color is hard to see in these pics as they were taken with a cell fone

Yup, it is sometimes difficult to judge the color from pics, as they seem to always differ somewhat from the actual colors. That is why judging from your first pic it seemed dark metallic green to me.

Its not just h2o2 its 35% h2o2 that was ordered by swim from a chem supplier

Not what I meant, I was wondering if you used H2O2/I2 or only H2O2, since you didn't specify that.

Like swims p-benzo seems to be bright yellow crystals that burn your eyes and nose just going near them but then it makes me wonder if swims just in disbelief because hes a newbee and doesnt have a shred of confidence.  I dont know just my two cents buts its prolly more like newbee rambling to many.

Well, that doubting when performing reactions the first time is only normal. It's only from experience you learn to be more confident in what you do is right. The way you describe it, it sure sounds like p-benzoquinone.

Or: You could steam distill it. Just add the crystals to enough water and distill. Quinhydrone will dissolve in boiling water, and the quinone will be carried over. This way you should get very pure p-benzoquinone.


wolfx

  • Guest
p-benzo appearance
« Reply #7 on: October 16, 2003, 05:02:00 AM »
From the Merck Index, 12th edition :

"Yellow monoclinic prisms"

I agree, the color should be bright yellow, looks like hydroquinone but yellow. I think usually we see a bit green-yellow because of quinhydrone ( ? ) contamination. Looks like you have a lot of impurities in your product.

I have been trying to make / purify p-benzo via dichromate ( SpiceBoy ), but I have had a lot of trouble also. The final product, after filtering, has a lot of Cr impurities and water, looks muddy, very green ( pea green ) and differently than pure p-benzo, is VERY water soluble. The green color is due I guess to Cr2O3. Yields are easily 140 %, what tells you there is a lot of impurities and H2O. I have tried to purify with DCM, and the final product superficially looks OK, nice yellow, just a hint of green color, dry powder, but there seems to be some residual impurity remaing or generated when using DCM. Twice I had strange results with the Wacker, lots of impurities, solid black tar, low yield, usually 30 % or so. In another occasion similar black tar showed up mixed with the freebase when xtaling, but washed away with acetone. Low yield, though. Benzene seems to work better but yields are low, also difficult to distill out when p-benzo concentration starts to increase. I had to use aspirator vacuum for the DCM as well as for the benzene.

If using the dichromate method, best technique seems to be to dry it WELL after filtering, let it stand inside a glass container with drierite for a few days, might have to change the drierite once or twice. Don't try to purify, use as it is and use a slight excess. I hit 65 % ketone yield on my first try, never was able to repeat that.

Also, black tar etc. never showed up, only when I tried to purify with DCM. Low yields with the Wacker, though.

I think the H2O2 method is a better deal, but I have never tried it myself. I have heard other bees have got quinhydrone instead of p-benzo, it might be very well what you get.

If you can buy it you will avoid a lot of headache, but be careful. I have ordered it once, they call me back and said they needed a statement from me or my company telling them what I was planning to use it for. I said I would do it, then called them back again, said please cancel it, they said OK, no problem. This was about two years ago.

Other bees comments will be very welcome, I have high interest in this topic.

homeslice

  • Guest
so whats the verdict?
« Reply #8 on: October 16, 2003, 05:20:00 AM »
I agree, the color should be bright yellow, looks like hydroquinone but yellow. I think usually we see a bit green-yellow because of quinhydrone ( ? ) contamination. Looks like you have a lot of impurities in your product.
Ive read that quinhydrone is dark colored, almost blackish. Theres nothing in there that is anyting but gold colored. When swim takes out about 2-3 crystals of that and applies a nice light to them swim can easily tell that they are 100% gold colored, kinda bright yellow. Swim followed the synth exactly word for word exactly and sat there the whole time to make sure everything went well. Twice Swim got the exact same thing, which makes swim think he did it right but swim would feel alot more reassured when a senior bee says "yes homeslice thats p-benzo and it looks great"
So whats the final verdict here? P-benzo or quinhydrone or p-benzo w/ quinhydrone? Should i proceed to the wacker with this?

Whats really on swims mind is that when he does the wacker, if he gets poor yields, he doesnt want to turn around and blame his benzo and then be pissed off at himself for not getting a 100% reassurance that it was benzo to start with...   ;D

wolfx

  • Guest
To go or not ?
« Reply #9 on: October 16, 2003, 05:47:00 AM »
If you have only quinhydrone as contaminant, I don't think it is a serious problem, just use a slight excess of p-benzo and you would be OK. But, I suppose quinhydrone contamination would make your p-benzo kind of green-yellow, maybe a lot green, and should be still kind of nice, dry, powdery. You said it looks gold colored, that I don't understand.

I guess you might get a low yield with the Wacker, but I don't feel like I an experienced enough to tell you go for it or not. Up to you, maybe ask some of the more experienced guys. Please post your results, I am interested in the H2O2 method as well.

Good luck,

W.

chilly_willy

  • Guest
and that color is..?
« Reply #10 on: October 16, 2003, 08:02:00 AM »
Im not sure what the big question is regarding this.  Is it yellow or isnt it?  It looks very black green in that picture.  Pure benzo is canary yellow--as in post-it-note yellow; smiley yellow; legal pad yellow.  Over oxidized benzo, or benzo that has been left out in air turns green. If its not bright yellow its not pure.  Why dont you inquire on how to get it nearly reagent pure bright yellow?  In one of my posts- I got quite descriptive on how to do this. How long, and at what temperature was it reacted at? What were your reactants, and at what ratios?  Crystallization procedure?? Ask these questions and then post the pictures of your blindingly bright, no questions asked benzo.
This reaction is great once the kinks (if there are any) are ironed out...


blaaky

  • Guest
just to chime in...
« Reply #11 on: October 16, 2003, 08:46:00 AM »
a scaled down mm benzo wacker was run with the p-benzo from this post

Post 457743

(blaaky: "p-benzoquinone via h2o2 results", Newbee Forum)


The resulting ketone looks and smells good, amination pending.
Note: previous benzo wackers were run with the pea-green benzo purchased from a photographic supply and had positive amination results.

blaaky


homeslice

  • Guest
Its all yellow. There is no green.
« Reply #12 on: October 16, 2003, 04:40:00 PM »
Its all yellow. There is no green. Im going to try to borrow my friends digital camera later today to get better pics of it.

Why dont you inquire on how to get it nearly reagent pure bright yellow?
Ive been looking everywhere for an answer to this!
It was reacted at the exact temperatures that overclocks method says. Swims reactants for the first time were a 1x scale of overclocks method and the second time swim did a 2x scale with the exact same results. Swim recrystalized with 91% almost boiling ISA. Let it cool to room temp. Placed in fridge. Placed in freezer for an hour. Then vacuum filtered and rinsedwith ice cold ISA. I'd get into more details now but i got 2 classes to go to  :(

My two roommates agree with me that the color is definatly the color of gold.
Ill try to dig up a digi camera later.

chilly_willy

  • Guest
Re: clean benzo (Rated as: good idea!
« Reply #13 on: October 16, 2003, 06:46:00 PM »

clean benzo
(Rated as: good idea!)     Bookmark  Reply     

First of all this reaction can be scaled up if you are prepared to drop the flask in cool water when things start to heat up.. Also- It is well to let the reaction continue to just slightly boiling for some time. When you think you are ready to crystallize drop the whole flask in the freezer for an hour or so until you get quantitative amounts of YELLOW benzo.  Take everything over the the buchner and suction filter.. being sure to use plenty of ice cold alcohol to wash everything well.  Use saran wrap as a dam to get the last of the liquid out.  At this point your benzo should be yellow with a hint of red...canary yellow if you washed it well.  If it still has a red tint/flecks..you can recrystallize from denaturated, methanol or even water to get perfectly bright yellow crystals.  Remember as well that you can use methanol, denaturated, or isopropyl for the reaction solvent.  Afterwards put your damp Xtals in a shallow tupperware container within a larger one with CaCl..and in a few hours you will have nice large bright Xtals that dont huff and puff when you drop them in that giant 5L...







homeslice

  • Guest
recrystalize
« Reply #14 on: October 16, 2003, 08:27:00 PM »
Swim chose ISA to recrystalize because another bee said it bee ok.

Chilly can u post a picture of ur p-benzo? Or can anyone post a picture of their p-benzo? Swim needs something to compare his to. All the benzo posts on here talk about how its either old or photo-grade benzo. Swim needs a picture that is good p-benzo displaying these bright yellow crystals that swims heard so much about.

homeslice

  • Guest
Ok new pic
« Reply #15 on: October 16, 2003, 10:24:00 PM »
New picture. There are other ones but they are too large. This was a much higher resolution but swim had to shrink it so it didnt take forever.



MUCH better higher resolution picture. Now.. can someone give swim a definate ID on what the fuck it is? ;D  Is it good to use for the wacker or is it going to hurt my yields significantly
See why i referred to it as gold colored now?

Midi

  • Guest
an idea..
« Reply #16 on: October 17, 2003, 01:00:00 AM »
Dunno what you got there, but I wouldn't use it.

As far as I know, P-Benzo is not listed, nor watched in small amounts, and I have seen it being offered recently in the US. I am not saying you should buy some, but really you should. It doesn't look like you have more than 500g there, and 500g amounts aren't going to raise any eyebrows. Recently, a friend of a friend sucessfully imported 5kg, not a single problem. If you have good safrole, it shouldn't be wasted. Get the right stuff. What you have may work, but yield would suffer so much it wouldn't be worth the wasted paladium.


homeslice

  • Guest
im confused then what does p-benzo look like
« Reply #17 on: October 17, 2003, 01:04:00 AM »
I did the synth twice with all lab grade chemicals exactly as it says and got the same results? Is the synth wrong then if thats not p-benzo?

Midi

  • Guest
P-Benz Pic
« Reply #18 on: October 17, 2003, 01:21:00 AM »



wolfx

  • Guest
Looks OK
« Reply #19 on: October 17, 2003, 01:30:00 AM »
This one looks like the real McCoy.

lugh

  • Guest
Melting Point
« Reply #20 on: October 17, 2003, 01:48:00 AM »
The melting point of p-benzoquinone is 116°C, the melting point of quinhydrone is 172°C, as you would all know if you read the Vogel's article on page 745 of the file available on Rhodium's page  :)  Why play guessing games without definitive information, when you can use the time tested methods of organic chemistry  ;D


homeslice

  • Guest
hmm
« Reply #21 on: October 17, 2003, 02:24:00 AM »
that doesnt look anything like swims.
So... now what does swim do? Should swim recrystalize again? Before recrystalization, swims was in powder and clumps like that picture of the good benzo. It wasnt that color however, it was much darker with yellow flakes.

If thats p-benzo then wtf is swims? Any suggestions? And if someone will answer this, can that bee explain to swim why swim yielded that crystal stuff?

Did you synth that via h2o2 and i2? Has anyone synthed via h2o2 and i2 and gotten positive results? Im absolutely fuckin baffled i mean i did exactly as the synth prescribed down to a fuckin T, even sat there and watched the temp the whole time?????? I cant imagine what could have gone wrong? After raising the temp to 50 degrees for 3 hours and letting it stir and complete the reaction, at what point is it done? What should swim look for near the end of the reaction to tell swim its time to take the heat away and start to cool the flask? I know the synth says that it should only be yellow specs floating in a dark red solvent. Swims however looked like yellow specs suspended in a thicker blackish/really dark red solution.
Now im all depressed i thought swim did somethin right  :(  :(  :(

Midi

  • Guest
Did you synth that via h2o2 and i2?
« Reply #22 on: October 17, 2003, 02:39:00 AM »
Did you synth that via h2o2 and i2?

No, that was purchased from a major chemical supply company. I have no experience making it, thankfully. The consistancy of P- Benzo is so fine that upon opening a container of it, fine clouds of it sometimes tend to fill the work space, and your nasal passage, causing burning and triggering my already allergy prone ass into a sneezing frenzy. I couldn't imagine fucking with it anymore than you already have too.

Do some research on it, look in the merk for it's uses, and use the fuckin google search engine, and also

http://www.froogle.com




Chimimanie

  • Guest
Read this thread: Post 374595 I am 100% ...
« Reply #23 on: October 17, 2003, 11:07:00 AM »
Read this thread:

Post 374595

(Cyrax: "p-benzoquinone synthesis", Chemistry Discourse)


I am 100% confident that what you have is quinhydrone.

I am also 100% confident that what Midi have is benzoquinone.

The iodine/h2o2 reaction didnt work for SWIM, never went to the quinone, he was stuck at the quinhydrone stage, just like you. It doesnt matter if they are gold or green or dark, those all are quinhydrone, as it look metallic.

Try the V2O5 synthesis from the above thread, 100% easy, not a way to fail, and it give even yellower product than the one from Midi.

You cannot recrystallise quinhydrone to have benzoquinone, you must reoxidize it, that is the only solution, and dont do it with h2o2/i2, it doesn't work.

homeslice

  • Guest
So is there anything i can do with my ...
« Reply #24 on: October 17, 2003, 06:36:00 PM »
So is there anything i can do with my quinhydrone?

lugh

  • Guest
Steam Distillation
« Reply #25 on: October 17, 2003, 08:51:00 PM »
From the Vogel's article you were advised to read  ;)

p-Benzoquinone (" quinone ") is obtained as the end product of the oxidation of aniline by acid dichromate solution. Industrially, the crude product is reduced with sulphur dioxide to hydroquinone, and the latter is oxidised either with dichromate mixture or in very dilute sulphuric acid solution with sodium chlorate in the presence of a little vanadium pentoxide as catalyst. For the preparation in the laboratory, it is best to oxidise the inexpensive hydroquinone with chromic acid or with sodium chlorate in the presence of vanadium pentoxide. Naphthalene may be converted into 1: 4-naphthoquinone by oxidation with chromic acid.
A fairly general procedure consists in coupling a phenol or naphthol with a diazotised amine, reducing the product to an aminophenol or aminonaphthol, and oxidising the hydroxy compound with acid ferric chloride solution. This method is illustrated by the preparation of (3 (or 1 : 2)-naphthoquinone When a solution of, say, 1 g. of hydroquinone in 4 ml. of rectified spirit is poured into a solution of 1 g. of quinone in 30 ml. of water, quinhydrone, a complex of equimolecular amounts of the two components, is formed as dark green crystals having a glistening metallic lustre, m.p. 172°. In solution, it is largely dissociated into quinone and hydroquinone. Quinhydrone is more conveniently prepared by the partial oxidation of hydroquinone with a solution of iron alum.


The article states that quinhydrone dissociates into quinone and hydroquinone in solution, so steam distillation should separate it, the hydroquinone should bee left behind  :)


homeslice

  • Guest
Im finding alot of steam distillation posts...
« Reply #26 on: October 17, 2003, 11:30:00 PM »
Im finding alot of steam distillation posts about essential oils but from my understanding I set up for a regular distillation. Add distilled water and the quinhydrone/p-benzo mix together in the distilling flask. And heat til it boils. Do everything like a normal distillation, and in the receiving flask that water will cool to allow the p-benzo to crash out. Right? Ive been trying to use the fuckin search engine but havent really found anything about steam distilling quinhydrone to yield p-benzo. Also, will this be worth the effort by the look of those crystals? I mean is swim going to yield 2 grams of p-benzo?

lugh

  • Guest
Last Chance
« Reply #27 on: October 18, 2003, 02:40:00 AM »

Ive been trying to use the fuckin search engine but havent really found anything about steam distilling quinhydrone to yield p-benzo.




You're not going to find anything about this procedure, since apparently no bee has ever done this before  ;)  You've now got the chance to actually contribute something useful to this site, imagine that  ;D  There are numerous posts about steam distillation of various volatile substances here, and a very good section in the Vogel's 3rd Edition available at:

https://www.thevespiary.org/rhodium/Rhodium/chemistry/vogel3.html



Considering the effect of quinone on tear ducts, it would be best to perform such a task with good ventilation  :)  Any more silly questions and you'll get some bad karma  8)   If you can't figure it out with what you've been told in this thread and what's available here and on Rhodium's page, you need to find a different hobby  ;D  :)  ;D




doktor_alternate

  • Guest
p-benzo
« Reply #28 on: October 22, 2003, 09:24:00 PM »
"As far as I know, P-Benzo is not listed, nor watched in small amounts, and I have seen it being offered recently in the US"

this is contrary to what i have come to understand. p-benzo IS
on the dea watchlist (i shouldnt need a ref for this) and some of those american companies that offer it even go so far as to state on their website: dea form required. beside the price quote for that chemical.

maybe you know a SPECIAL american chem supplier, or just have a good legit front buisness, but ive gone to looking to have it shipped into canada from china/ect...

homeslice

  • Guest
Swim sees exactly as you say with the DEA form
« Reply #29 on: October 23, 2003, 01:57:00 AM »
Swim sees exactly as you say with the DEA form required next to alot of photo chem sites. But whats more important is right next to warning the suppliers are selling it in very small ammounts, like 10grams. Swim understands that p-benzo is used in very small ammounts in photography, so how would one ever be justified in buying say a lb of it, unless p-benzo has other uses. Now that swims given up on having any success with the h2o2 method as h2o2 is apparently not strong enough to oxidize the hydroquinone(?), and apparently Sodium Chlorate, which is used via the V2O5 method, is harder to acquire than fuckin quinone itself; swims been reading a little bit more about p-benzo and found out that it seems that it is used in alot of agrochemicals. It appears that it is used in some fungicides. Have any bees had success sourcing p-benzo from an agrochemical supplier?

Swims also located a supplier that sells in 100gram lots of benzo along with other chemicals. Swims excitement at finding a distributor such as this was dampened as swim scrolled through their chemicals listed and found that they also sell AMT and DMT.  ;D  It might just be swim but it seems like this distributer is aimed at clandestine chemists. It also sells 7% i2 tincture for a really high price and right next to it, peanut oil??? If any bees have had success with this distributer, and you know which one it is, PM me please.

Midi

  • Guest
alternate routes
« Reply #30 on: October 23, 2003, 01:17:00 PM »
this is contrary to what i have come to understand. p-benzo IS on the dea watchlist

Ok, first off, HOW do you know this to be factual? And how do you know that there is even a "dea watchlist" ??

If it's really hard for you bees to get this stuff then look at the next easiest route. PdCl2 - CuCl2 and O2 arent that hard to obtain and wont burn the fuck out of your orfices when working around it.  ;)


homeslice

  • Guest
Swim doesnt believe in watchlists or whatever...
« Reply #31 on: October 23, 2003, 06:21:00 PM »
Swim doesnt believe in watchlists or whatever someone wants to call it. But swim has seen companys selling p-benzo requesting a "DEA Buyers Authorization Form". And right below that is the link to the DEA that allows you to apply for this form. Application of this form involves an on-site visit from a dea affiliate to verify your company.
Also swim contacted a distributer of p-benzo and questioned them about why p-benzo has this "strange dea form request" next to it. The answer received: "well im not exactly sure why but the dea contacted us and..."
So companys are watching p-benzo, and the h2o2 method of synthing benzo seems to fail many bees. How watched is Sodium Chlorate? Swims read posts on here that refer to how it can be used in bombs?

chilly_willy

  • Guest
cheap
« Reply #32 on: October 25, 2003, 02:40:00 AM »
If any source has a huge, strangely specific disclaimer or requires any type of mailed in form or special permission for a chemical...they aren't a source.  They are simply a re-layer of private information. This puts the bee in a compromising position which is totally avoidable. Let them sell to someone else..dont give them a cent. There are PLENTY of other guys with the same stuff out there.
Most photo companies dont bat an eye at selling 1-5 lb quantities of hydroquinone for $6/lb. This in turn can be converted nearly quantitatively into a VERY pure product. IMHO it pays to scrounge up a few pinches of Iodine, Tech grade H2O2, and some Isopropyl.  Much more efficient, and fool-proof than the O2.  Not to mention the fun, and satisfaction of producing your own reagents.


lugh

  • Guest
From Aniline
« Reply #33 on: October 25, 2003, 04:00:00 AM »
From Perkin's and Kipping's Organic Chemistry  :)

Quinone or benzoquinone is usually prepared by oxidizing aniline with potassium bichromate and sulfuric acid:

   Aniline (1 part) is dissolved in water (25 parts) and sulfuric acid (8 parts), and finely powdered potassium bichromate (3.5 parts) gradually added, the whole being well cooled during the operation; the product which is very dark colored, owing the the presence of aniline black, extracted with ether, the ether evaporarted, and the crude quinone purified by recrystallization from light petroleum or by sublimation


:)


homeslice

  • Guest
lugh: swim found a synth on google talking...
« Reply #34 on: October 25, 2003, 06:44:00 AM »
lugh: swim found a synth on google talking about using hydroquinone and KBro3. Not too scientific although.

 

(http://www.uni-regensburg.de/Fakultaeten/nat_Fak_IV/Organische_Chemie/Didaktik/Keusch/p16_ox_hydr_brom-e.htm)
Willy that was the idea. Make the benzo cuz theres no reason to ever take a risk at all ordering anything shady when it can be made, practically otc, easily. Swim read the synth with the h2o2 and i2 and figured it would be the best way to go since it seemed simple and it was discussed a pretty good bit on the hive. Well now swims done the synth exactly as specified 3 times and all swims gotten was quinhydrone. ??? The only thing different swim is doing is the setup.  Swims using
a 1 litre erlenmeyer with a 3" octaganol stirbar sittin in a waterbath stirrin at full speed most of the time. Swims usin a clasien to fit the addition funnel and therm obviously. Swims done the synth 2 times regularly, and 1 time at a 2 time scale up. After recrystalizaion the pic above is the same shit swims been getting consistently. The one time swim let the second 3 hour part of the synth stir at 45 degrees for close to 5 hours to make sure everything reacted. Still got the same thing. What the fuck is swim doin wrong?  :(  Is there any advice anyone can offer swim?

blaaky

  • Guest
more advice...
« Reply #35 on: October 25, 2003, 07:03:00 AM »
homeslice... I've done this synth only twice but both times I've had bright yellow p-benzo as the result. I kept records of everything I did exactly, I will type them up here when I get the chance...

One thing I remember off the top of my head:

My addition funnel was leaking h2o2 so I ended up dumping it all in within 5 or 10 minutes and the temp shot up very high... wait till I get the details. send me a pm to remind me.

Heres a pic of my 2nd synth:




chilly_willy

  • Guest
do this
« Reply #36 on: October 25, 2003, 02:14:00 PM »
Just add the H2O2 as fast as it will go in w/o boiling over.  Then keep your solvent at just near boiling (60-75) for about 1 1/2 hours.  All reactants should be liquified.  Put flask in freezer- yellow crystals.


homeslice

  • Guest
blaaky that looks like a human brain lol
« Reply #37 on: October 25, 2003, 07:17:00 PM »
blaaky what the fuck is that lol

swims always looked like a dark red, dark maroon mixture, with the yellow swirlies ive read about. it never really went completely watery like liquified. it always stayed somewhat thicker, kind of like um.... oversaturated water with sugar, ya know how it gets like syrupy? Chilly can you do a little writeup of what your explaining in your last post? What should i follow from the original synth? Does swim need to keep temp at 30 degrees for 3 hours or is that retarded? so keep it at 60-75 for 1 to 1.5 hrs. I have a good sep funnel should i add dropwise just fast enough to put the temp at 60?
 
Could someone explain how this is working? I understand the h2o2 is oxidating the hydroquinone to form quinhydrone, then with further oxidation and agitation the quinhydrone forms para-benzoquinone. How does the temperature affect the turn from quinhydrone into p-benzo?

chilly_willy

  • Guest
grr..
« Reply #38 on: October 25, 2003, 07:57:00 PM »
Not trying to be a grouch or anything, and I'm no moderator- but this thread is starting to run itself ragged. Everything you wanted to know about this reaction is either linked or described rather thoroughly within the posts.  I also already pasted a writeup about this reaction within this thread a few posts back.....


lugh

  • Guest
Study More Chemistry
« Reply #39 on: October 26, 2003, 01:34:00 AM »

How does the temperature affect the turn from quinhydrone into p-benzo?




C_W is right, the answer to this question can bee found in a thread from the last few weeks, namely

Post 464029

(Pimpo: "reflux and reactivity?", Newbee Forum), as well as many other posts about kinetics, and at the beginning of any initial organic chemistry course  ::)  You are attempting to practice organic chemistry, and to succeed in that pursuit, you need to understand some basic principles, which you could learn by following some of the very helpful links posted in the sticky threads, or downloading Vogel's as suggested  :)  Thus this thread is being locked, you need to start reading a lot more  ;)