fusso
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Using conc H2SO4 + NaCl to chlorinate alcohols?
Can I make 2-chloropropane/isopropyl chloride from iPrOH, conc H2SO4 and a chloride salt like NaCl?
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Pumukli
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Can we make i-propyl-chloride from HCl and i-propanol?
(Because your suggested method is basically this. But it would probably give worse yield because reportedly H2SO4 reacts with i-propanol and makes an
undefined mixture of smelly and coloured products.)
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fusso
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Quote: Originally posted by Pumukli  | Can we make i-propyl-chloride from HCl and i-propanol?
(Because your suggested method is basically this. But it would probably give worse yield because reportedly H2SO4 reacts with i-propanol and makes an
undefined mixture of smelly and coloured products.) |
Yea I originally thought H2SO4+NaCl would give a higher
conc of HCl/Cl- and lower conc of water to drive the rxn forward. But what "smelly and coloured products"?
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DavidJR
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Use zinc chloride + HCl (Lucas' reagent)
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fusso
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Why, if it wont work?
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Pumukli
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It will work, (Lucas' reagent.)
What won't work (probably) is your original idea (mixing sulfuric acid, NaCl and i-propanol together) because in these days it was reported in another
thread that conc. sulfuric acid and i-propanol together yields a purplish, gasoline smelling crap.
Lucas' reagent is known to work with secondary alcohols.
Edit:
"Crap from attempt to make isopropyl salicylate, something interesting happened"
This is the thread where the incompatibility of sulfuric acid and i-propanol was mentioned.
[Edited on 16-12-2019 by Pumukli]
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DavidJR
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It even works on primary alcohols, albeit slowly and requires heating.
Now, for tertiary alcohols, plain ol' HCl will usually do the job by itself.
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clearly_not_atara
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Do this:
https://www.sciencemadness.org/whisper/files.php?pid=615083&...
But know that LR on iPrOH is complicated by the fact that iPrCl has a very low bp.
H2SO4/NaCl will not work; sulfuric esters, oligomers and HCl form.
[Edited on 04-20-1969 by clearly_not_atara]
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fusso
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What oligomers? polypro(pyl)ene?
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AvBaeyer
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Sulfuric acid is not necessarily fatal to isopropanol. Isopropyl bromide can be made from H2SO4 and NaBr. It is all in the details about how the
reaction is run.
See the following SM posts:
http://www.sciencemadness.org/talk/viewthread.php?tid=5725
There has also been a discussion on the preparation of isopropyl chloride. I am surprised that no one bothered to look.
http://www.sciencemadness.org/talk/viewthread.php?tid=16441
AvB
[Edited on 18-12-2019 by AvBaeyer]
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Cou
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| Quote: Originally posted by Pumukli | It will work, (Lucas' reagent.)
What won't work (probably) is your original idea (mixing sulfuric acid, NaCl and i-propanol together) because in these days it was reported in another
thread that conc. sulfuric acid and i-propanol together yields a purplish, gasoline smelling crap.
Lucas' reagent is known to work with secondary alcohols.
Edit:
"Crap from attempt to make isopropyl salicylate, something interesting happened"
This is the thread where the incompatibility of sulfuric acid and i-propanol was mentioned.
[Edited on 16-12-2019 by Pumukli] |
The gasoline smelling crap only forms with high concentrations of sulfuric acid, when added too quickly without cooling mixture in ice bath during
addition. I successfully did a fischer esterification which used a w/w concentration of 32.9% sulfuric acid and 67.1% isopropyl alcohol. the sulfuric
acid was added slowly in an ice bath w/ stirring. Reflux went perfectly.
The gasoline crap formed when i tried to make a concentration of 42.7% sulfuric acid w/w, and added it all at once with no ice bath. For some reason
the cooling and stirring makes a huge different, even though they both get heated to the BP of isopropyl alcohol during reflux anyway.
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