On the old Board there was a thread called OTC Benzyl Chloride which someone named "ymir" detailed this procedure.
I looked on the old board and did a search, but the post was lost.
From what I remember he/she dryed the toluene and the calcium hypochlorite then added an excess of the Ca(OCl)2 and heated it, careful not to explode the mixture. If i remember there was addition of light as well.
Ymir didn't detail the drying of the Ca(OCl)2, but said he had to dig up some old references. By the way, drying Ca(OCl)2 is dangerous.
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I found the old thread "OTC Benzyl Chloride" on the hive.txt zip files from Wizard X. Here is the repost:
Author Topic: OTC Benzyl Chloride
ymir
Member posted 07-04-99 03:40 PM
Tales of Jotunheim-I
The frost giants were getting restive. Summer was coming, and their
ice supply was dwindling. Loki, having tired of the tank, and its
difficulties, decided to give USP 1280612 a try. He thanks Spiceboy
for publicizing it, and Scooby for posting his problems with it.
Many details were missing, so Loki did his homework, and discovered
that about twenty years ago, in the interests of making HTH
foolproof, Olin-Matheson ceased completely drying HTH. Loki
determined that dry HTH was stable up to at least ninety degrees
fahrenheit, and that in days of yore, before commercial
availability, had been dried in the laboratory for six days in the
dark, in a dessicator using an oil pump. Loki tared the weight of
the calcium hypochlorite in a three pound HDPE margarine container,
gently placed it in his vacuum dessicator, covered it with an old
towel, and started the pump. Periodically, Loki checked the weight
of the HTH under low illumination. By the next day, the HTH ceased
to lose any more weight. The lid was placed on the dry HTH to keep
it that way. Commercial toluol was distilled, a fresh dry flask
being attached after the temperature reached 110 degrees
centrigrade. After distillation was finished, the dried toluene was
poured into an acetone dried wine jug, along with a few ounces of
anhydrous magnesium sulfate. Loki then assembled his chlorination
apparatus. A 5L flask filled with 1365 g of dry HTH and 1575 ml of
toluene, fitted with a thermometer and a condenser, with the end of
the condenser filled with dried cotton and anhydrous calcium
chloride. A stopper was inserted into the end of the condenser, with
fuel line connecting sequentially to two gallon jugs, the first
empty, with a stopcock, and the second filled with tap water. A
polyethylene milk jug filled with washing soda solution, cut out to
accomodate a funnel completes the gas adsorption apparatus. The oil
bath was heated up slowly to 85 degrees, and a heat lamp was then
directed into the flask. The exothermic reaction proceeds best
around 105 degrees, so the heating bath must be kept cooler until
the end of the reaction. HCl gas begins to bubble out of the
toluene. Once the reaction temperature reaches 105 degrees, the heat
lamp is turned off. It is well to wire down the empty jug's stopper,
and to use the stopcock to release the vacuum, when necessary. After
a few hours of slow bubbling, a rapid evolution of HCl will occur.
This will be absorbed by the apparatus. The stopcock is used toward
the end of the reaction, to prevent sucking back, and at other times
while adjusting the heat. The liquid is decanted, and the solids
filtered under vacuum. The excess toluene is distilled, and then
three pints of 99% isopropyl alcohol is added (at least 1230ml), to
deal with the toluene/benzyl chloride azeotrope. The
toluene/isopropanol azeotrope distills at 80.6 degrees centrigrade,
and then the excess isopropanol distills at 82.4 degrees
centrigrade. The benzyl chloride was then distilled using a Perkin
triangle (Vogel's), with a glass packed claisen head, to change
flasks without releasing the vacuum on the distillation flask.
Depending on the strength of the vacuum, the benzyl chloride
distills somewhere around 100 degrees centrigrade. The yield is
around 500 ml, which may be dried with anhydrous calcium chloride or
5A molecular sieve, if it is to be used in a Grignard. The toluene
may be recovered from the azeotrope by flooding it with water, the
toluene will seperate. However one chooses to execute this, no iron
should contact benzyl chloride, as it will catalyze decomposition.
Scooby Doo
Member posted 07-06-99 08:01 PM
That is an excellent piece of work if do say so myself. Loki you
most definitely have bigger balls than I on drying the hypochlorite,
good call. The yield is sensational, but I noticed that Loki used
commercial grade toluene. I have dreamed of cleaning commercial
grade toluene via Vogel (Thanks again jimwig) of thiopenes (sp?). I
dreamt of being totally surprised on the amount of crap that the
sulfuric acid wash removed, with yields following suit and going up.
I know what you mean in regards to the azeotropes, I tended to see
this with water and benzyl chloride distilling over at 80 deg.
However the distillate would quickly break down (minutes) due to the
water.
Its interesting to see that Loki still experienced the violent
reaction with the massive amount of HCl being released. I would have
thought anhydrous conditions would have gotten rid of this problem.
I have dreamt of multiple runaway reactions which tended to get very
violent. When one empties the flask one can see stones, which are a
brown/black colour where the reaction took place. I believe mixing
might get rid of this localised reaction and keep it more steady.
Its probably due to the HCl being hygroscopic and collecting water
out of the atmosphere which inturn reacts with the Calcium
hypochlorite.
Scooby
ymir
Member posted 07-06-99 08:20 PM
Loki doesn't think that it is water, he says the gas observed was
definitely HCl. Loki thinks that its just the course of this
particular reaction to go bananas at a certain point. The apparatus
described can deal with this easily, and could be scaled up further.
He says its vital to have a drying agent in a tube, or the end of
the condenser. Loki is aware of the thiophene removal technique,
half of what he knows he got from Vogel's. Next time, he'll try it.
Loki says the tank method won't even work well with thiophene left,
so this method is superior in more than one way.As far as drying
HTH, its in Inorganic Syntheses, Vol. 3; as long as the temperature
and light level constraints are observed, its absolutely safe. Its
been almost a hundred years since any one had to do this, so digging
was necessary. Methanol will remove the toluene also, buts its
azeotrope is only 25% toluene, instead of 42%. Now its on to the
next battle, OTC P2P!
Loki
Member posted 07-07-99 02:01 AM
Me? I havent even started looking at first rxn yet..... still
learning verry basics....But with a name like Loki its got to be
good
------------------
It aint got a thing if it aint got that swing...
ymir
Member posted 07-07-99 04:03 AM
They say imitation is the sincerest form of flattery, so please try
to keep yourself under control. Someone who is not ymir, known as
Loki (not to be confused with this newbee), wants the Hive to also
know that everything used in this procedure must be clean! Certain,
unknown as of yet organic and inorganic materials have intiated the
explosive decomposition of calcium hypochlorite, and thus, as usual,
cleanliness is next to not only godliness, but additionally,
ungodliness. Also, the reference, Kirk-Othmeyer, states that HTH is
dried at 90 degrees Centrigrade, so any environmental temperatures
should be safe. Another factor that Loki wants the Hive to know is
that Loki has the distinct feeling that sunlight (with its UV) is
the main initiator of these explosions, so appropriate precautions
must be taken.
ymir
Member posted 07-07-99 06:23 AM
Loki also wants to point out that the heat lamp used was an
infra-red lamp.
Rhodium
Administrator posted 07-07-99 06:04 PM
Where can I find the original patent text, as well as a write-up of
Scooby's adventures? I'd like to put this on my page.
ymir
Member posted 07-08-99 08:34 AM
Old US Patents are available from the Patent Office in Washington,
D.C.; and the older Patent Depository Libraries:
University of the State of New York, Albany, NY
Georgia Institute of Technology, Atlanta, GA
Boston Public Library, Boston, MA
Grosvenor Library, Buffalo, NY
Chicago Public Library, Chicago, IL
Cincinatti Public Library, Cincinatti, OH
Cleveland Public Library, Cleveland, OH
Ohio State University, Columbus, OH
Denver Public Library, Denver, CO
Detroit Public Library, Detroit, MI
Linda Hall Library, Kansas City, MO
Los Angeles Public Library, Los Angeles, CA
State Historical Society Library, Madison, WI
Milwaukee Public Library, Milwaukee, WI
Minneapolis Public Library, Minnieapolis, MN
Newark Public Library, Newark, NJ
New York Public Library, New York, NY
Franklin Institute, Philadelphia, PA
Carnegie Library, Pittsburg, PA
Providence Public Library, Providence, RI
St. Louis Public Library, St. Louis, MO
San Francisco Public Library, San Francisco, CA
Seattle Public Library, Seattle, WA
Oklahoma State University, Stilwater, OK
Toledo Public Library, Toledo, OH
Obviously, the first places to look in Europe would be at Oxford,
the Sorbonne, Berlin, Rome and Moscow.
Rhodium
Administrator posted 07-08-99 07:39 PM
You silly, I can order any patent from the university library, I
just thought I could save the $10 fee, as well as a lot of work if
you could provide me with the essential parts of the patent, as you
obviously have a copy of it yourself.
ymir
Member posted 07-08-99 08:53 PM
Actually, as I indicated in the E-mail I sent you, I don't have a
copy of the patent.
CHEMMAN
Junior Member posted 07-22-99 05:37 AM
Am dreaming of chlorinating toluene with gas Have Vogel-any further
advice on cleaning up the toluene that he doesnt mention,as even
though I have supposedly high grade toluene,am not convinced.Thanks
for any help!
CHEMMAN
Junior Member posted 07-22-99 05:42 AM
Sorry for the double post ,but what does HTH stand for
?hypochlorite?? Sorry for the ignorance too !! CheersCHEMMAN
ymir
Member posted 07-22-99 07:07 AM
HTH is Olin-Mathesonspeak for calcium hypochlorite!
Scooby Doo
Member posted 07-24-99 07:37 PM
Rodium here is the abstract ref which might help (CA 1918 vol.12
(nov-dec) p2573)
C.C. Loomis U.S. 1,280,612, Oct 1. In chlorinating toluene to form
benzyl chloride, the toluene and dry bleaching powder are heated
together to a temp. of about 105 deg in the absence of acid or other
reagent for decomposing the bleaching powder. This treatment avoids
the formation of by-products, if about equal amounts of toluene and
bleaching powder are used. Larger proportions of bleaching powder
effect more complete chlorination of the toluene but produce also
other products such as benzal chloride and benzotrichloride.
There was no write up on my behalf of this reaction, just a lot of
mistakes. Ymir has definitely done the hard yards with this reaction
getting it up and running.
Ymir I was interested to hear the use of an infra red lamp, I always
believed that UV is what helped the normal method of chlorine gas
chlorination of toluene. I can totally agree with you on the non use
of any UV lamps around kwazy chlorite, but why the infra red?
Scooby
ymir
Member posted 07-25-99 02:41 AM
Loki says the heat lamp raises the temperature to the required 105
degrees, then is shut off, because the reaction is exothermic! Using
only one heat source (oil bath) causes the reaction to get too hot!
Scooby Doo
Member posted 07-25-99 07:34 PM
Yeah I know what you mean, reactive little sucker!
The acetaldehyde + BzCl is looking promising, the caustic smelling
oil (suspected P2Pol) from the above reaction was oxidised using
Sodium Dichromate in H2SO4 yielding a very sweet smell indeed. I
will hopefully dream some more on this soon.
Scooby
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The easy way to make benzyl chloride is with a glass coffeepot filled with equal weights (not equimolar weights) of toluene and chlorine pool shock, Ca hypochlorite. The tablets work OK, though the huge biscuit type, if you get those, probably should bee broken up a bit. Expose one at a time to the air, and bust it quickly with a hammer, before it gets water out of the air. Use a water bath to allay your fears about thermal runaway, unless your heat source will reliably keep the rxn under 100°. Stretch plastic wrap over the lid of the coffee pot, to keep from losing too much toluene to evaporation. I think the actual knee of thermal runaway is the 113° boiling point of toluene, but as has been emphasized above, give it some margin. I like to keep it below 100°, myself: I don't mind spending a bit more time in the reaction to avoid breaking glass, even if it is only a Goodwill coffeepot.
This one is for outside, unless your fume hood gives you nerves of steel. Note that simply changing the proportions of Ca hypochlorite to toluene, from 1:1 by weight to 1.5:1 or as I prefer 1.66:1, will give you a product containing an increased proportion of benzal chloride compared to benzyl chloride. Benzal chloride is conversible to benzaldehyde by simple acid or basic hydrolysis, though to get benzaldehyde from benzyl chloride needs a little oxidative boost, e.g. chromic acid. Also note that MnO2/aq H2SO4 will convert a mixture of both benzyl chloride and benzal chloride to benzaldehyde.
The fractionation of toluene, benzyl chloride, and benzal chloride is quite sharp, and gives no trouble determining when to take the fractions. I usually just take the tolly (amounting to 2/3 to 3/4 of the filtrate) off at atmospheric pressure first. Then vac is applied for the benzyl chloride and then the benzal chloride. The still dregs are largely the useless benzotrichloride, discard the dark remnant.
Just watch this one for ~ 4 hours, and it's not such a big deal. The moderate bubbling you see coming off the hypochlorite is the chlorination reaction, it is not the toluene boiling. If the toluene boils, write it off. Watch from upwind. Benzyl chloride is a nasty irritant.
Post 304720 (https://www.thevespiary.org/talk/index.php?topic=6546.msg30472000#msg30472000)
(SideArm: "Benzal Chloride, and Benzaldehyde's Hidden Power", Chemistry Discourse)
Post 36700 (https://www.thevespiary.org/talk/index.php?topic=7588.msg3670000#msg3670000)
(CHEM_GUY: "Re: benzyl chloride from hypochlorite salts", Chemistry Discourse)
US 1280612 (http://l2.espacenet.com/dips/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US1280612&ID=US+++1280612A1+I+)
(http://l2.espacenet.com/dips/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US1280612&ID=US+++1280612A1+I+)
a half a pints a half a pound a half a world a half a round
Sidearm n. Flask neck tube.
I don't think that anybody should attempt this procedure unless they can be sure that the calcium hypochlorite and toluene are anhydrous !
Also commercial calcium hypochlorite (pool shock) contains appreciable amounts of calcium hydroxide and calcium chloride as well.
If like swim in the UK, one can purchase benzyl alcohol easily from photographic suppliers, the concentrated hydrochloric acid method https://www.thevespiary.org/rhodium/Rhodium/chemistry/benzylchloride.html (https://www.thevespiary.org/rhodium/Rhodium/chemistry/benzylchloride.html)
should be safer.
John Lennon - Working Class Hero