rannyfash
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chloroformate ester synthesis
so i have a rough guess, could lone electron pairs on an oxygen in an alcohol attack a dipole positive carbon in phosgene, purely theoretical since
the intense toxicity has already been suspected of killing a member already (r.i.p myfanwy94)
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DDTea
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Yes, you can synthesize chloroformate esters this way. See page 4 of this little pamphlet: http://www.buss-ct.com/e/company/publications/reaction_techn...
Benzyl alcohol + COCl2 --( -15 C, 1.5 hr )--> BzO(C=O)Cl (97%)
This touches on a whole category of chemical reactions called phosgenations. It's actually very useful chemistry in spite of the toxicity which,
when handled with the proper lab infrastructure, is tolerable. Look into a book titled "Phosgenations--A Handbook" by Catarca and Eckert.
EDIT: Let me kindly refer you to the sciencemadness posting guidelines, specifically parts 4 and 6: http://www.sciencemadness.org/talk/viewthread.php?tid=19143
[Edited on 4-23-12 by DDTea]
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
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rannyfash
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thanks for the link, greatly appreciated, i will probably also post all my topics in beginings from now on since im not judging which topic it belongs
to, its a shame how some of the most usefull reactions involve very toxic reagents that could not possibly be conducted in a rural area safely
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BromicAcid
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They're useful for the same reasons they are toxic. Their intense reactivity is often the reason for their toxicity. Personally I love making
chloroformates with phosgene, there are not many reactions that you can add two reagents together neat and come back with a product >99% pure with
a 99% yield without even the need for distillation.
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rannyfash
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it does sound tempting, what health and safety protocols do you follow?
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DDTea
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Tempting? Rightly or wrongly, most chemists go out of their way to avoid using phosgene in lab-scale syntheses. It would be completely reckless and
irresponsible to perform a phosgenation at home. If you have to ask about health and safety protocols, then they probably are not already in place.
This cannot be an afterthought. Some things are simply inappropriate for a domestic environment.
[Edited on 4-24-12 by DDTea]
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
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rannyfash
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tempting as in working with such an exotic, usefull and deadly toxic reagent. i agree it would be completely reckless to attempt in a rural or urban
environment, "what health and safety protocols do you follow?" when i asked this i am asking what do they do as they have made it seem like they work
with phosgene, it does not suggest that i follow none myself, but im just curious to know what people have done and survived.
the most dangerous chemistry i have done is bromine distillation, quickfit apparatus with silicone grease in the joints, and the reciever the vent was
vented through concentrated NaOH, i also had a moldex respirator, goggles, and elbow length nitrile gloves, with a bucket of weak sodium thiosulphate
standing by just incase. i can assure you i carried out the upmost care but i was a little irresponsible carrying it out in my garden and if there had
have been a leak im sure it would have been an easy issue to resolve with a small release of bromine into the surrounding environment, "Some things
are simply inappropriate for a domestic environment" yup, shame though, its why i say tempting as i know phosgene is too toxic to have anywhere near
other people
know any other method of creating chloroformate esters?
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ScienceSquirrel
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Mood: Dogs are pets but cats are little furry humans with four feet and self determination! 
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Chlorination of methyl formate
http://www.sciencemadness.org/talk/viewthread.php?tid=7289
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