chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
Reductions using Ca metal
I'm dehalogenating a heterocyclic aromatic amine that has a Cl atom on one of the phenyls. I put the free base form of the amine in ethanol with
equimolar (actually slight excess) of Ca metal. The paper calls for granular metal which I don't have. Rather I have chunks of Ca as it was supplied.
I tried breaking these up in an N2 filled plastic bag but the bag was broken through before any Ca broke.
Attachment: Dehalogenation of Aromatic Halides Using Metallic Calcium in Ethanol.pdf (68kB)
This file has been downloaded 625 times
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
|
WGTR
National Hazard
Posts: 971
Registered: 29-9-2013
Location: Online
Member Is Offline
Mood: Outline
|
|
Depending on how big your chunks are, perhaps clamping them into a small vise under oil, and drilling them slowly with a sharp bit. I couldn't say
how to wash the shavings afterwards, though.
|
|
|
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
I was stirring the mixture with a flea in a small Erlenmeyer. I changed stir bars in favor of a larger (1.25") one and the Ca started breaking up. I'm
hopeful.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
|
zed
International Hazard
Posts: 2284
Registered: 6-9-2008
Location: Great State of Jefferson, City of Portland
Member Is Offline
Mood: Semi-repentant Sith Lord
|
|
Again....Ball milling. Sponenberg has plans for a machine, in his book. Or, Harbor Freight offers a fairly inexpensive "Rock Tumbler". With a
little tweaking, it should be able to do the job.
|
|
|
phlogiston
International Hazard
Posts: 1379
Registered: 26-4-2008
Location: Neon Thorium Erbium Lanthanum Neodymium Sulphur
Member Is Offline
Mood: pyrophoric
|
|
Dan Vizine in his 'thorium thread' used a file:
http://www.sciencemadness.org/talk/viewthread.php?tid=29927#...
If you need larger amounts, ball milling seems a good method to try, but you should be extremely cautious then because the calcium will presumably
become pyrophoric.
-----
"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer |
|
|
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
I have harbor freight ball mill. I need better balls for it. The chrome plated one get de-plated too quickly.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
|
dermolotov
Hazard to Others
Posts: 114
Registered: 13-12-2014
Location: Toronto, Canada
Member Is Offline
Mood: Free
|
|
This is what I did to make Potassium powder. Then I flushed out moisture in a vacuum flask and mixed it with hexanes. Then poured the solution through
a funnel and put it in a vacuum dessicator for an hour.
Okay potassium powder. Don't see why it shouldn't work with calcium. Of course, if you can get calcium, just get calcium turnings to make things
easier.
|
|
|
phlogiston
International Hazard
Posts: 1379
Registered: 26-4-2008
Location: Neon Thorium Erbium Lanthanum Neodymium Sulphur
Member Is Offline
Mood: pyrophoric
|
|
You must not have handled calcium metal before then.
It is a lot harder than potassium. Probably you can deform it, but don't expect to be able to flatten or extrude it with a vise like you can with
sodium or potassium.
I once had great trouble cutting slivers of it of a larger piece with a knife. A saw is a more appropriate tool.
[Edited on 14-12-2014 by phlogiston]
-----
"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer |
|
|
dermolotov
Hazard to Others
Posts: 114
Registered: 13-12-2014
Location: Toronto, Canada
Member Is Offline
Mood: Free
|
|
Quote: Originally posted by phlogiston  | You must not have handled calcium metal before then.
It is a lot harder than potassium. Probably you can deform it, but don't expect to be able to flatten or extrude it with a vise like you can with
sodium or potassium.
I once had great trouble cutting slivers of it of a larger piece with a knife. A saw is a more appropriate tool. |
I have - but only in powdered form.
Couldn't he just vice grip it in oil and file it down in oil as well?
|
|
|
phlogiston
International Hazard
Posts: 1379
Registered: 26-4-2008
Location: Neon Thorium Erbium Lanthanum Neodymium Sulphur
Member Is Offline
Mood: pyrophoric
|
|
Yes, that should work. Ca also does not oxidase as quickly as the alkali metals, which helps too.
-----
"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer |
|
|
dermolotov
Hazard to Others
Posts: 114
Registered: 13-12-2014
Location: Toronto, Canada
Member Is Offline
Mood: Free
|
|
What would be the quickest way of removing the layer of oxidation on calcium powder/turnings?
|
|
|
zed
International Hazard
Posts: 2284
Registered: 6-9-2008
Location: Great State of Jefferson, City of Portland
Member Is Offline
Mood: Semi-repentant Sith Lord
|
|
Not Calcium Hydride? Used to be cheap, cheap, cheap. Now, surplus cans of CaH, seem to be gone, gone, gone.
|
|
|
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
Using big chunks took longer but it worked; just stirring the mixture for a couple of days
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
