Talk:Birch reduction
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I just included a bit more detail regarding kinetic vs. thermodynamic protonation of the anion intermediate. Gly 23:55, 3 February 2007 (UTC)
[edit] Opening statement is midleading?
"This reaction provides an alternative to catalytic hydrogenation, which is extremely difficult to perform on aromatics, due to the stability of the extended conjugated system." Here are the problems with this statement: (i) catalytic hydrogenation of arenes is not really extremely difficult and (ii) catalytic hydrogenation of arenes tends to go all the way, one rarely obtains cyclohexadienes. Thus I propose to revise this statement to the effect that Birch is a method for making cyclohexadienes. Comments or suggestions are welcome.--Smokefoot 13:47, 1 August 2007 (UTC)
- I agree and I made the change. Is this acceptable?Silverchemist 05:58, 20 August 2007 (UTC)
[edit] Mechanism cleanup
"....and alcohol such as ethanol and tert-butanol can be used instead of ammonia."
This is incorrect - alcohols cannot act as a substitute to ammonia. In fact, an alcohol is necessary to facilitate a Birch recuction (the alcohol acts as a proton source). The text under "reaction mechanism" is also incorrect - ammonia is NOT (and cannot be) deprotonated under Birch conditions (it is far easier to protonate ammonia than it is to deprotonate it!). —Preceding unsigned comment added by 220.233.115.217 (talk) 08:36, 17 January 2008 (UTC)
- Well you can whine about the problematic section or you can do something about it (with a reference). --Smokefoot (talk) 14:33, 17 January 2008 (UTC)
- My esteemed colleague of course means he is inviting you to assist in the wikipedia effort: My March tells me you are only half right, so we are looking forward to your edits. V8rik (talk) 17:27, 17 January 2008 (UTC)
From March (6th ed.), p1068: "Thus the function of the alcohol is to supply protons, since with most substrates ammonia is not acidic enough for this purpose. In the absence of the alcohol, products arising from the dimerization of 110 are frequently obtained."
OK, I'll concede a slight error on my part, but I was not that far off, no? Upon re-readiing the article I also feel there is scope for expansion; specifically a section discussing the effect of substituent groups upon regioselectivity. —Preceding unsigned comment added by 150.203.34.37 (talk) 02:56, 18 January 2008 (UTC)
- I would agree the article needs an update on the purpose of the alcohols and expanding the article is more than welcome. V8rik (talk) 21:17, 18 January 2008 (UTC)
[edit] Regioselectivity
- has a discussion of the regioselectivity of the second protonation been omitted intentionally? Whilst the explanations can be quite wooly I think it would merit discussion... Seansheep (talk) 17:45, 19 March 2008 (UTC)
