Comments on: NaH: Magical Oxidizing Pixie Dust

By: Science in the Open » Blog Archive » P ≠ NP and the future of peer review

Tue, 10 Aug 2010 13:20:31 +0000

[...] and see it radically out-perform traditional pre-publication peer review. The rapid demolition [1, 2, 3] of the JACS hydride oxidation paper last year (not least pointing out that the result [...]

By: TCCG

TCCG — Thu, 05 Aug 2010 23:06:57 +0000

oh wait.. both papers were withdrawn!

By: TCCG

TCCG — Thu, 05 Aug 2010 23:05:56 +0000

this sort of thing happens every-freaking-where. How sad

By: MSG

MSG — Thu, 26 Nov 2009 00:42:49 +0000

This may have been mentioned (or implied) by other comments which I haven’t read (I got through 50%… but then gave up), but for NaH to be the oxidant, you would either need to have to reduce Na+ to Na, or at least some sort of Na complex in which the Na has an oxidation state less than +1. I’m pretty sure that if they say stoichiometric formation of sodium metal in the reaction they would probably see that. either that or H- gets reduced to H-2, or at least an oxidation state less than -1, which is ridiculous to say the least.

The first thing I thought of when I read it was the massive acceleration you get with the anionic oxy cope compared to the oxy cope. the cope is obviously a different reaction to an benzylic oxidation, but I’m presuming the NaH is simply accelerating the reaction.

My money is on oxygen being the oxidant rather than peroxides. I don’t think you can get an equivalent or more amounts of ether peroxides to form even if you leave the solvent exposed to air for days, speaking from previous experience. I’m not saying that the small amounts of peroxides aren’t dangerous, but just that you can’t possible get that much. I’m assuming that these guys stored their THF under Ar, so even if it’s old, you can’t get an equivalent of peroxides in there.

By: Carbon-Based Curiosities » Blog Archive » Reduction of sodium hydride by fluorine gas in vacuum.

Wed, 25 Nov 2009 03:10:23 +0000

[...] IT is ON again: Na Promoted Aerobic Oxidation of Alcohols to Ketones, Tet. Lett., 2009, in press [tx mt]. [1] [...]

By: Kaz

Kaz — Wed, 02 Sep 2009 03:12:34 +0000

Refer S. Ohta et al, Synthesis 1983, 291.
They said various benzylic alchols and aldehydes were oxidized in good yield using NaH with a catalytic amount of pyrazole in THF under air at room temperature. The paper suggests that Na2O2 is generated from O2 and NaH and which is the real oxdant.
At least, Chinese chemists had to refer the paper.

By: excimer

excimer — Mon, 24 Aug 2009 05:45:32 +0000

there’s a method in modern catalysis called the “just put it all in” method, whereupon things get a lot hotter and more reactive when you dump more stuff in. I mean, only putting a little in will get the desired result, but things go a lot faster if you put more in, and sometimes, for maximum rate-enhancement you need to put it all in.

…penis

By: Ψ*Ψ

Ψ*Ψ — Mon, 24 Aug 2009 05:34:10 +0000

hi, welcome to CBC. the first rule of teh blog is that ~~you cannot talk about fight club~~ you can’t be an asshole here.
srsly, we all know what JACrapS meant. don’t be that guy.

By: Luke

Luke — Mon, 24 Aug 2009 04:35:57 +0000

Not everyone agrees with your definition. Some add the specific requirement that a considerably substoichiometric amount of the proposed catalyst be used.

By: Luke

Luke — Mon, 24 Aug 2009 04:18:29 +0000

MgSO4. [Mg]2+[SO4]2-