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drfro2
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'newbie' Chlorination Of Toluene via Calcium Hypochlorite
Hey everyone,
Im new to this forum and wouldn't mind some help from people with a greater chemistry understanding than myself,
I would like to make Benzyl Chloride via Toluene and Calcium Hypochlorite,
What i would like to know is,
What light is best used in this reaction?
What are the risks involved? such as explosions and or gas
What is the recommended equipment/apparatus for this synthesis?
How long does the reaction take?
How will i know i have Benzyl Chloride when im done?
And at what temperature will the reaction safely take place?
Also if someone could explain the steps for this procedure for it would be much appreciated 
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entropy51
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Welcome Dr Fro. Abandon hope all ye who enter here.
It's generally considered bad form to post without searching first. Practically everything imaginable has been discussed here in the past.
Click "Search" at the top of the page, enter benzyl chloride in the search box, select "subject only" and "all forums" and you will be truly amazed by
how many threads are returned for your viewing pleasure.
Feel free to visit the forum library, accessible from the home page. There are many textbooks and lab manuals available for FREE download that will
answer many of your questions. Enjoy!
Once you have some of the basics down, you could then ask specific questions that are less "newbie".
I hope this information is helpful to you!
Better to remain silent and appear a fool than to open your mouth and remove all doubt.
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drfro2
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I was surprised to get such a fast reply lol,
I am aware that when entering a new forum people like newbies to read through already existing material, hence excluding the need for constant
re-discussion of topics,
I have read mostly all the threads floating around this topic but there are so many conflicting opinions,
What im looking for is a synthesis thats tried and tested by someone on here, I could not find this because everyone seems to have a different
opinion, I could not find a post where someone discussed their materials, equipment, steps and yield,
this is why i started this post,
However if i just missed this and there is a post like that, please link me to it
I am aware there are easier ways to do this such as with benzyl alcohol and hydrochloric acid,
But seeing as toluene is is $10 a litre here and Ca(ClO)2 is around $15 per kg i tought i would give this reaction a go,
After reading for a few weeks im confident i can complete this reaction, i just need more of the specifics.
Any information and discussion would be much appreciated, not looking to start arguments
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entropy51
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Dr Fro! You said "After reading for a few weeks im confident i can complete this reaction". But you also said
"What is the recommended equipment/apparatus for this synthesis?
How long does the reaction take?
How will i know i have Benzyl Chloride when im done?
And at what temperature will the reaction safely take place?"
Seems like your confidence may have gotten ahead of your knowledge!
Have you read Gatterman and Vogel in the Forum Library? Most of the questions you asked are answered in Gatterman!
You are right about BnOH + HCl being the best route! Chlorination of tolune is not to be attempted lightly.
For starters, did you look at this https://www.sciencemadness.org/whisper/viewthread.php?tid=10...
[Edited on 3-7-2009 by entropy51]
Better to remain silent and appear a fool than to open your mouth and remove all doubt.
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drfro2
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entropy51,
I asked those questions to be sure what i have been reading is fact, i dont intend to be taking this reaction lightly and am aware that chemisty
involves risks, some of which are far greater than others.
All i am asking for are specifics, so i can carry out the reaction in the safest way possible, with a decent factual understanding of the task at
hand,
If my confidence was ahead of my knowledge i would have already attempted this without the proper understandings and quite possibly had a disaster,
I posted the thread asking for help for this reason, in no way do i think i know all there is to know, this is why in my first post i wrote ''wouldn't
mind some help from people with a greater chemistry understanding than myself''.
So obviously i need help, and am asking for specific steps from anyone who has successfully performed this reaction and has the proper understanding
of the ideal conditions this reaction is to take place,
Also i tried that link and for some reason i wont allow me to access the page,
So yes i am confident i could carry out this reaction IF i was properly equipped for the task, had an understanding of tried and tested reaction
conditions and also full understanding of the risks and hazards involved,
This is why im here, FOR HELP
I dont intend to be trying anything without a proper understanding, and when i do finally attempt this reaction it will be on a small scale so if
anything does go wrong the risk is lowered.
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not_important
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The thread entropy51 is Len's excellent write-up on chlorinating toluene and hydrolysis of those chlorides. Until you've read that, I suspect few here
will be interested in further helping you.
The link he gave was via https access, and as sciencemadness signs its own security certificate your browser probably didn't like that; a decent
browser should have given you a message to that effect and allowed you the open to accept the certificate.
the plan old http link is http://www.sciencemadness.org/talk/viewthread.php?tid=10256
[Edited on 3-7-2009 by not_important]
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drfro2
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not_important,
Thankyou for the reply,
The link works thankyou 
Reading now!
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entropy51
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OK, that link opens up for me. It's the Benzyl Cl thread by Len1 in Prepublications in the Special Topics Forum. It shows some of the glassware
setups you would need. What type of glassware do you have? You really need glass with ground joints for this prep; corks don't take it well. You
also need a fume hood! Chlorine is dangerous and BnCl is a very efficient tear gas.
Basically you heat toluene (flammable!) to reflux in a flask with a reflux condenser and a gas inlet tube passing into the toluene. With exposure to
sunlight or sunlamp you pass in Cl2 gas for several hours. The top of the relux condenser is connected to a trap containing aqeous NaOH to absorb the
fumes. Finally you distill off the product under vacuum, there is a forerun of unreacted toluene; Gatterman has details.
Taking everything apart and cleaning the glassware is a bear. It must be done inside a hood.
If you plan to generate the Cl2 using Ca hypochlorite, you should consult the ten page long chlorine thread here. The problem with using hypochlorite
is that O2 is also generated, and that may very well screw up your reaction.
I'm really not trying to be argumentative, but you are likely to find more help here if you show some initiative to find out things on your own, using
for example the forum library.
Thanks not_important, for pointing out the problem with https.
[Edited on 3-7-2009 by entropy51]
Better to remain silent and appear a fool than to open your mouth and remove all doubt.
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drfro2
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Thankyou for the information,
The glassware i currently have is varied somewhat, i have 2 x liebig condensers 1 x allihn condenser and 1 x graham condenser, 2 x 1 litre vacuum
flasks, 2 x 1 litre rbf, 2 x 500ml rbf, 2 x 2 litre rbf, also a few different adapters like 3 way clasien and vacuum, 2 separatory funnels and just
other general glass, Most have ground glass joints,
Glass isn't a problem for me to obtain so getting correct tools for the job isn't too hard,
The thread is very detailed and well written, definately alot more specific than another synthesis which i have read,
This is why i asked for help becuase i had read elsewhere that clacium hypochlorite and toluene could be added to a flask, with the presence of blue
light, heated to 105C and refluxed,
It sounded far too simple to be true, does that method even work?
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entropy51
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Adding Ca hypochlorite directly to toluene? I was afraid you were thinking of that and I should have warned you. The hypochlorite is a class I
oxidizer and I certainly wouldn't want to try that. I think it might do something unpleasant or dangerous, but I doubt it will give benzyl Cl.
Someone who knows better can correct me if I'm wrong.
I thought you would like Len1's writeup. There is a tremendous wealth of knowledge archived on this forum (also some that's less than accurate) so
spend some time digging around and finding the good stuff. Again, welcome!
And heed Len1's warnings about the chlorinated toluenes. My advice is to get some experience with more friendly sytheses before trying this one.
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drfro2
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Advice taken!
Thanks guys
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Sedit
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" I think it might do something unpleasant or dangerous, "
You get a nasty runaway.
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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drfro2
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Also,
For this reaction instead of a 3 neck rbf can i use a 4 inch neck reaction flask with 3 mouth adapter?
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Sauron
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Do you have a fume hood, goggles, respirator, etc?
Benzyl chloride is Not Nice. Toxic and lachrymatory.
Where I live it is a restricted dhemical by the MOD.
The best light is UV so sunlight, sun lamps, bright unfiltered quartz-iodide floodlights with heat glass plate removed skk work. BUT what is good for
rxn is bad for your eyes and epidermis. Do not expose yourself to US even reflected or indirect.
Braille chem books are hard to come by.
Sic gorgeamus a los subjectatus nunc.
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not_important
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Adding to the comments on direct mixing and heating of calcium hypochlorite and toluene, consider the following...
While hypochlorites themselves are oxidisers, in https://www.sciencemadness.org/whisper/viewthread.php?tid=10... the production of calcium chlorate from calcium hypochlorite. Heating chlorates
and organic compounds together seems like a bad idea.
As Len noted in his write-up, chlorination of the aromatic ring is much more likely to occur in the liquid phase than in the vapour phase. Given that
pool grade calcium hypochlorite isn't exactly reagent quality, there's a good chance it contains small amounts of one or more transition metals that
catalyse hologenation of the ring. This means that your product will likely contain chlorinated toluenes (2; 4; 2,4; and 2,6 at least) and toluene
derivatives chlorinated both on the ring and the methyl group.
And commenting on light sources, as Len notes you want light in the range of around 350 to 490 nm. Clear globe mercury vapour lamps put out a goodly
segment of their light in this range, while generating far less waste heat than quartz-halogens.
[Edited on 3-7-2009 by not_important]
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drfro2
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Sauron,
No i do not yet have my saftey equipment or fume cupboard, i am still in the process of buying all of my equipment,
I have begun reading len1's thread on the chlorination which is very interesting but still looks out of my league at the moment,
As for the toluene and calcium hypochlorite, has anybody actually completed this? or is it just a case of dont believe what you read on the internet?
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Sauron
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Another way to get to PhCH2Cl is by chlorination of benzul alcohol. A qide variety of reagents will work.
A third method is chloromethylation.
But NO method is a good idea unless/until you have the appropriate protective equipment.
Where on or off the Net does it say toluene can be alpha-chlorinated with calcium hypochlorite? I am not saying it is impossible. But it probably is
not the best choice even for OTC. I would put TCCA ahead of it, just as an example.
Sic gorgeamus a los subjectatus nunc.
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drfro2
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http://www.designer-drug.com/pte/12.162.180.114/dcd/chemistr...
Is where I initially read it, but after reading len1's post i can also see its from my huge misunderstanding of how the reaction works aswell,
I just typed in benzyl chloride synthesis into google and thats how i found it.
[Edited on 3-7-2009 by drfro2]
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Sauron
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I wish that site wouls shrivel up and die. And if you are their habitue, that explains why you are so intent on benzyl chloride, next step
phemylacetonitrile, after that phenylacetic acid, and then P2P.
Son't expect any assistamce from me.
Sic gorgeamus a los subjectatus nunc.
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drfro2
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Actually when i typed benzyl chloride synthesis into google,
That is one of the sites that came up,
I was actually looking for a synthesis to do with OTC chemicals when i saw a post someone had made on another science forum that toluene could be used
to produce benzyl chloride,
Toluene can be bought at every hardware store here so i began to search the synthesis, the more i read i found it interesting and it looked
challenging so i set out to find more information hence coming here,
Also if you are implying what i think you are, I would be on a drug forum not here!
I came to this forum looking to learn and for help from people who know about real chemistry! not to be a cook and land myself in jail for a good 25
years!
[Edited on 3-7-2009 by drfro2]
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Nicodem
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Drfro2, the literature is full of examples of toluene alpha-chlorination with Cl2 and several other reagents, yet you opened a thread without
providing a single reference (this you are only allowed to do in the Beginnings section where I'm moving the thread) and asking questions that were
already answered innumerable times, even on this forum. Keep in mind that you will unlikely get any useful reply without showing your effort and
maturity. Considering this reaction simple when it is quite likely to give you a serious injury is a bit irresponsible in the context of your lack of
doing a literature search.
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Nicodem
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Thread Moved
2-7-2009 at 23:11 |
entropy51
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Yeah, that's the second time this week someone has suggested adding a strong oxidizer to neat toluene. The other was chromyl chloride.
Must be time for nominations for the Darwin Award
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Sedit
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LOL what are you suggesting entropy Im still alive and kicking so can I get to be
runner up?
It was all very small scale though because it seemed like a bad idea to me also.
[Edited on 3-7-2009 by Sedit]
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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entropy51
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No No, Sedit. You were right on with your warning!
I couldn't even convince myself to try Ca(OCl)2 + toluene in a test tube on a 1/2 gm scale. I'm not good at predicting reactions, but this one
doesn't pass the smell test.
But I knew better about the CrO2Cl2 because it's in the literature that a couple of chemists were blinded doing that back in the 19th century. And
they used solvents too...just the wrong ones.
As Sauron says, there are old chemists, and bold chemists, but no old, bold chemists. I'm pretty old myself, and proud of it.
I sometimes wonder if the mods shouldn't be deleteing the dangerous stuff, instead of the name calling.
P.S. Woelen, to clarify I meant the plain stupid dangerous stuff you refer to, not the reactions that just require extra caution. And I agree with
you that the forum members are generally very good at pointing out the hazards.
[Edited on 3-7-2009 by entropy51]
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woelen
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| Quote: | | I sometimes wonder if the mods shouldn't be deleteing the dangerous stuff, instead of the name calling. |
No
it would not be good at all if the moderators delete dangerous stuff. What is dangerous and what is not? Who decides for us? But when something plain
stupid dangerous is posted without any warning, then it is much better if any of us (non-moderator) members tells and warns about that and then the
moderators can decide what they want to do with the member or even move the thread to detritus (which is not the same as deleting it completely!).
I also sometimes do dangerous things (such as making chlorine azide ) but when
I do so, I know that I am doing and I take measures to reduce the risk (most of the time the measure is simply using very small amounts of chemicals).
In this particular thread there are warnings about the dangerous nature of Ca(ClO)2/toluene mixes and that is a good thing. I personally believe that
the sciencemadness community is very good at regulating the spreading of all kinds of stupid/dangerous information and giving good and realistic
warnings when stupid/dangerous things are posted.
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