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trilobite
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Have you tried to hydrolyze the substance? You should have no problems identifying the benzyl alcohol.
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Klute
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Unfortunaly, I didn't have time to finish, so the recrysatllized material is yet to be filtered ffrom the mother liquor. It's still in the RBF, under
Argon, in the freezer. But from a very rough guess, the mp seems to be quite high compared to the theoritical mp of the aldehyde. I will caracterise
the substance when I isolate it, and see if it's the benzyl alcohol or not. But TLC on the DCM extarct before removal of the solvant indicated it
wasn't the alcohol or the starting material (the supposed chloride). So the enigma is yet to be solved. If only I could do a NMR on it. Next week or
later I will be able to get IR spectrums of the supposed chloride and isolated product normally.
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Klute
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Update: I've finally filtered the recrysatllized material, giving small beautifull white shiny needles. A rough mp seems to indicate a value close to
the starting material (supposed chloride), a little on the low side though a rustic method was used as I'm not at work. It also has the same odor when
melted. So it's definatively not the aldehyde. The sommelet hydrolysis went exactly like the different describtions I've read. So maybe it wasn't the
chloride after all. The mp is still too high to be the alcohol. I'll do a TLC on it when I'll have time, to compare it with the crystals that were
used for the sommelet, and the alcohol. I don't get it. I really don't see what else the oxidation could have produced. The starting material is of
unquestionnable purity/identity.
Any ideas?
When I'll get back onto the 4-oxoTEMPO project, I'll try a oxydation on the same material and compare the products. I can't figure out what to do
otherwise, not being able to access either NMR or IR in near futur. 
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LSD25
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Klute,
Here is a fairly complex (above my head) overview of how to oxidise the benzyl halide to benzaldehyde in fairly good yield, under PTC conditions (via
NaOAc => AcO ester =NaOH=> BnOH =NaOCl=>BnO), one version of which is even undertaken in one pot (although at a substantial reduction in
yield).
Satrio & Doraiswamy, 'PTC; A New Rigorous Mechanistic Model for Liquid-Liquid Systems' (2002) 57 Chem Eng Sci 1355 {http://tinyurl.com/yslhfh}
For those of you who like such things, there is a very involved explanation of the mechanisms and mechanics of the reactions taking place, ie. this
does not appear to be a 'dodgy' type of article.
Whhhoooppps, that sure didn't work
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Klute
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Thanks for that, quite a complete article indeed.
To be honest, I'm quite lost as to what was produced during the TCCA oxydation; I'm planning on continuing this project with TEMPO-derivatives
catalysis, although this has been put aside for the moment...
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