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This article seems to specific in only discussing the nitration of aromatic compounds. Nitration can be performed on other molecules, such as alcohols. For example, the nitroglycerin page describes its synthesis as the nitration of glycerin.-- 24.16.148.75 21:15, 10 July 2006 (UTC)
Heh, while I was just making a suggest I went ahead and tried my hand at doing an edit. I've discovered a few things; it's one thing to stand in front of a group of people with a whiteboard and pontificate on the subject but it's an entirely different thing to try and type out a viable explanation, no wonder so few people write textbooks, and that listing substituent groups is somewhat pointless, perhaps that section should just be ommitted in favour of a summary? Although anyone who isn't familiar with the terminology could be a bit baffled by anything less. I'm also thinking I should do a few diagrams. GreatMizuti 14:35, 21 July 2006 (UTC)
"Substituents such as other NO2 groups have an electron pair donor effect which deactivates the reaction"
Nitro groups are strong pi and sigma electron withdrawers. This sentence makes no sense at all. Donor should be replaced with withdrawer. Also one does not activate or deactivate a reaction, there is a mess up with the lingo too. You catalyze or retard a reaction. The author of this sentence should be familiar with the meaning of the latter word well enough.
"Nitration can be activated by substituents such as amino"
WRONG! Depends on the conditions. An amine (aniline) easily donates its lone pair to an electrophile (like nitronium) or and acid (nitric, sulfuric [avoid using harsh conditions for nitration of electron rich arenes], etc.) that's used for catalyzing the formation of nitronium cation. A thumb rule: amine groups NEVER activate a ring for nitration unless you play some tricks (and usually go through a non-amine intermediate [may be formed in-situ]). This holds true for other "activated" arenes, including phenols under more unlikely conditions. —The preceding unsigned comment was added by 81.213.65.144 ( talk • contribs) .
Amino groups most definitely activate an benzene nucleus towards nitration - the nitration of 2,4- or 2,6-dinitroaniline to 2,4,6-trinitroaniline(picramide) can be done under much milder conditions than those required for benzene or toluene. I also think the article should emphasise the difference between nitration, where a proton is replaced by NO2, and nitrolysis, where other leaving groups (ie, COCH3, C(CH3)3, Cl, Si(CH3)3 etc.) are replaced.
The first scheme has an error in it.
I think the highest/top red arrow should be coming from the bond rather than going to the bond and ending at the oxygen. The way it looks now is suggesting it will form a double bond. — Preceding unsigned comment added by 94.214.148.76 ( talk) 15:41, 29 November 2011 (UTC)
So in the last step the h2o comes and picks up the h, i dont think this is what happens, its the o-oso3h that does to form h2so4 because h2so4 was a catalyst and can't be consummed... Philoleb ( talk) 21:30, 11 December 2011 (UTC)
Sulfuric acid is a strong acid and is essentially completely ionized in aqueous solution. The nitration mixture is typically a mixture of nitric acid (65 % w/w) and sulfuric acid, with no added organic solvent. -- Rifleman 82 ( talk) 22:27, 11 December 2011 (UTC)
ok theen would the so4 be the one that picks it up? and also when the No2 is attached to the benzene is it nitronium or nitrite Philoleb ( talk) 22:31, 11 December 2011 (UTC)
btw french wikpedia shows nitration as i first said, http://fr.wikipedia.org/wiki/Nitration just look at the diagrams. Philoleb ( talk) 22:34, 11 December 2011 (UTC)
The base can be sulfate, bisulfate or water. I'm not sure which one is preferred, but I don't suppose it really matters in the grand scheme of things. -- Rifleman 82 ( talk) 00:01, 12 December 2011 (UTC)
Is there enough research available to warrant a section devoted to the methods of nitration other than nitric acid/sulphuric acid mixtures?
Nitric acid/phosphoric acid mixtures look promising. There are also a few articles on nitrate salt/phosphoric acid mixtures.
http://jcsp.org.pk/index.php/jcsp/article/viewFile/1924/1357
http://pubs.acs.org/doi/abs/10.1021/ac60142a031
http://pubs.acs.org/doi/abs/10.1021/jo01034a063
http://www.springerlink.com/content/l736226872157485/
-- SlapChopVincent ( talk) 00:46, 4 June 2012 (UTC)
This article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||
|
This article seems to specific in only discussing the nitration of aromatic compounds. Nitration can be performed on other molecules, such as alcohols. For example, the nitroglycerin page describes its synthesis as the nitration of glycerin.-- 24.16.148.75 21:15, 10 July 2006 (UTC)
Heh, while I was just making a suggest I went ahead and tried my hand at doing an edit. I've discovered a few things; it's one thing to stand in front of a group of people with a whiteboard and pontificate on the subject but it's an entirely different thing to try and type out a viable explanation, no wonder so few people write textbooks, and that listing substituent groups is somewhat pointless, perhaps that section should just be ommitted in favour of a summary? Although anyone who isn't familiar with the terminology could be a bit baffled by anything less. I'm also thinking I should do a few diagrams. GreatMizuti 14:35, 21 July 2006 (UTC)
"Substituents such as other NO2 groups have an electron pair donor effect which deactivates the reaction"
Nitro groups are strong pi and sigma electron withdrawers. This sentence makes no sense at all. Donor should be replaced with withdrawer. Also one does not activate or deactivate a reaction, there is a mess up with the lingo too. You catalyze or retard a reaction. The author of this sentence should be familiar with the meaning of the latter word well enough.
"Nitration can be activated by substituents such as amino"
WRONG! Depends on the conditions. An amine (aniline) easily donates its lone pair to an electrophile (like nitronium) or and acid (nitric, sulfuric [avoid using harsh conditions for nitration of electron rich arenes], etc.) that's used for catalyzing the formation of nitronium cation. A thumb rule: amine groups NEVER activate a ring for nitration unless you play some tricks (and usually go through a non-amine intermediate [may be formed in-situ]). This holds true for other "activated" arenes, including phenols under more unlikely conditions. —The preceding unsigned comment was added by 81.213.65.144 ( talk • contribs) .
Amino groups most definitely activate an benzene nucleus towards nitration - the nitration of 2,4- or 2,6-dinitroaniline to 2,4,6-trinitroaniline(picramide) can be done under much milder conditions than those required for benzene or toluene. I also think the article should emphasise the difference between nitration, where a proton is replaced by NO2, and nitrolysis, where other leaving groups (ie, COCH3, C(CH3)3, Cl, Si(CH3)3 etc.) are replaced.
The first scheme has an error in it.
I think the highest/top red arrow should be coming from the bond rather than going to the bond and ending at the oxygen. The way it looks now is suggesting it will form a double bond. — Preceding unsigned comment added by 94.214.148.76 ( talk) 15:41, 29 November 2011 (UTC)
So in the last step the h2o comes and picks up the h, i dont think this is what happens, its the o-oso3h that does to form h2so4 because h2so4 was a catalyst and can't be consummed... Philoleb ( talk) 21:30, 11 December 2011 (UTC)
Sulfuric acid is a strong acid and is essentially completely ionized in aqueous solution. The nitration mixture is typically a mixture of nitric acid (65 % w/w) and sulfuric acid, with no added organic solvent. -- Rifleman 82 ( talk) 22:27, 11 December 2011 (UTC)
ok theen would the so4 be the one that picks it up? and also when the No2 is attached to the benzene is it nitronium or nitrite Philoleb ( talk) 22:31, 11 December 2011 (UTC)
btw french wikpedia shows nitration as i first said, http://fr.wikipedia.org/wiki/Nitration just look at the diagrams. Philoleb ( talk) 22:34, 11 December 2011 (UTC)
The base can be sulfate, bisulfate or water. I'm not sure which one is preferred, but I don't suppose it really matters in the grand scheme of things. -- Rifleman 82 ( talk) 00:01, 12 December 2011 (UTC)
Is there enough research available to warrant a section devoted to the methods of nitration other than nitric acid/sulphuric acid mixtures?
Nitric acid/phosphoric acid mixtures look promising. There are also a few articles on nitrate salt/phosphoric acid mixtures.
http://jcsp.org.pk/index.php/jcsp/article/viewFile/1924/1357
http://pubs.acs.org/doi/abs/10.1021/ac60142a031
http://pubs.acs.org/doi/abs/10.1021/jo01034a063
http://www.springerlink.com/content/l736226872157485/
-- SlapChopVincent ( talk) 00:46, 4 June 2012 (UTC)