Talk:Organoaluminium chemistry

Latest comment: 4 years ago by Bernardirfan in topic Confusing valency and oxidation state

Preparation

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In the part on the preparation of the compounds the next statement is made:

Industrially, simple aluminium alkyls (Me, Et) can be prepared by alkylation of aluminium powder:
    2 Al + 3 CH3Cl → (CH3)3Al2Cl3
The compound (CH3)3Al2Cl3 is called a sesquichlorides because on average, each Al centre has 1.5 chloride. These mixed halides can be converted to the triorganoaluminium derivatives by thermal redistribution:
   (CH3)3Al2Cl3 + 3 Na → (CH3)6Al2 + 3 NaCl 

To me in the second reactien tree methylgroups apear out of the sky. Who solves the problem? T.vanschaik (talk) 22:01, 6 February 2011 (UTC)Reply

It should read (according to the cited reference, Ullmann's):
2R3Al2Cl3 + 3Na → 3R2AlCl + Al + 3NaCl
3R2AlCl + 3Na → 2R3Al + Al + 3NaCl
Overall, this becomes:
2R3Al2Cl3 + 6Na → 2R3Al + 2Al + 6NaCl
This can be simplified to:
R3Al2Cl3 + 3Na → R3Al + Al + 3NaCl
If you want it to reflect the fact that many R3Al compounds are dimers, you can put a half in:
R3Al2Cl3 + 3Na → ½R6Al2 + Al + 3NaCl
Or you can double everything else:
2R3Al2Cl3 + 6Na → R6Al2 + 2Al + 6NaCl
Ben (talk) 23:39, 6 February 2011 (UTC)Reply

Carboalumination chemistry

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One might quibble about which sources to cite regarding this chemistry, but the deletion of the zirconocene catalyzed process is unjustifiable. This is a reaction taught in first-year graduate courses in total synthesis, and it has been used hundreds of times for natural product total synthesis since the 1980s when this reaction was discovered. Efforts to use the thus produced organoaluminum reagents also contributed to the subsequent Nobel prize winning development of sp2-sp2 cross-coupling by Negishi and others.

I have no personal stake in this, other than ensuring that Wikipedia covers in an unbiased manner. This reaction may not seem important to the coordination chemist, but it is parochial to consider that as the only legitimate POV.

I would be happy argue this case further or to discuss which particular sentences to keep or discard.

Ymwang42 (talk) 01:22, 30 July 2016 (UTC)Reply

If the method is so important, then find a review that discusses it. The WP:SECONDARY pathway is not only in the Wikipedia mindset, it provided editors a way to verify WP:NOTABILITY. Readers of Wikipedia do not consult Wikipedia to glean details, they are here to get an overviews. Blogs and real journals are excellent venues for the details. --Smokefoot (talk) 13:08, 30 July 2016 (UTC)Reply

Confusing valency and oxidation state

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The section "Low valent organoaluminium compounds" should be called "Low oxidation state organoaluminium compounds". Valency and oxidation state is not the same. The valency of aluminium in tetraalkyldialane R2Al—AlR2 is 3, but its oxidation state is 2. The valency of aluminium in tetracyclopentadienyltetraalane tetrahedrane (CpAl)4 is 3, but its oxidation state is 1. Bernardirfan (talk) 10:52, 7 July 2020 (UTC)Reply