Jor
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recrystallise [Co(NH3)5Cl]Cl2
Today i made some of this complex. Pictures are here, but it is in Dutch, so hard to read for most, but the names of the reagents should be familiar:
http://www.amateurchemie.nl/viewtopic.php?f=20&t=127
Now I washed my product with cold distilled water, but it may after all been not too smart as maybe some ligand exchange has occured (water replacing
Cl(-)), and it would have been smarter to dry the crystals by pressing in filter paper , instead of EtOH/Et2O washes, as I do not seem to have very
nice crystals now. But the last picture is not the dry crystals yet, they are drying now.
Anyway, when i would want to recrystallise, from wich should it be done? Dilute (4M or so) HCl? Or just water? What do you recommend, or you think my
product is pure already? Anyone has experience with this, as I don't want to lose too much product as i want to use some for the synthesis of
nitropentaamminecobalt(III) chloride.
thanks
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kcl04
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oh wow I've never seen a salt that color! Very pretty. Is cobalt a carcinogen?
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UnintentionalChaos
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I have a procedure for the discussed complex in this thread: http://www.sciencemadness.org/talk/viewthread.php?tid=10368&...
The lab had us wash with ice water and alcohol. Don't sweat it. The product is probably pure enough. I still have those samples, just sitting in cheap
plastic bags. There has been no visible decomposition in almost a year, indicating that the complexes are quite stable.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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Jor
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Yes, I know, I have seen that page. That was why i made the thread, because I remembered those crystals should be dry and beautiful, but mine are not
as beautiful, and I don't see nice crystals.
Anyway, I will try to heat it at 100C now, it shouldn't decompose as I have seen a source where they dried the material at 120C.
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Jor
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Ok it is dry now.
I heated the solid at 70-80C for 3 hours.
It is completely dry now, nice freeflowing violet powder. The color is very hard to capture on picture, as in the light it will appear somewhat
lighter than in reality (see below), but when pictured in a much less lighted area, it will appear purple. A picture:
http://i405.photobucket.com/albums/pp133/Joris12345/P1100298...
You can see some granules but these can easily be crushed.
I am so attracted to coordination chemistry, as preparing the compunds is so much fun, there are so many complexes out there, and I like all the
change in colors.
Here just a picture I made some time ago:
http://i405.photobucket.com/albums/pp133/Joris12345/P1100302...
From left to right:
(NH4)2Cr3O10 , VOSO4.xH2O , Cu(en)2SO4, Co(en)3Cl3 , KCr(C2O4)2(H2O)2ยท2H2O , KVO4.2H2O , Cu(CH3COO)2.H2O , CoCl2 (anhydrous), NiSO4.6H2O (VERY
beautiful green, picture doesnt show this), trans-[Co(en)2Cl2]Cl , CuSO4 (anhydrous), K3CrO8, [Co(NH3)5Cl]Cl2 and Ni(NH3)4SO4.
I made all these myself except nickel sulfate and vanadyl sulfate (donated by woelen).
These are just a selection of some metal compounds I have. I'm so impressed by all the colors you can get. Who else, except woelen ofcourse (we all
know he is the one doing great work on this area  ) is really into making all
these compounds at home, or better said doing inorganic seriously? 
[Edited on 21-3-2009 by Jor]
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