falala
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preparation of salicylic acid from anthranilic acid
how can SA be synthesized from AA?
by diazo replacement? how's that?
any help will be really appreciated! thank you!
[Edited on 29-1-2009 by falala]
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sparkgap
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Seriously? I know a number of people who'd rather use the anthranilic acid for other purposes as it is not too easy to come by, and also because
salicylic acid can easily be had with no fuss.
sparky (~_~)
"What's UTFSE? I keep hearing about it, but I can't be arsed to search for the answer..."
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falala
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that's the thing. they want us to synthesize SA with AA
the reaction's diazotization and hydrolysis. do you know the intermediates of this reaction?
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panziandi
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Anthranilic acid would be diazotised with sodium nitrite/hydrochloric acid mixture at 0*C, the solution would then be hydrolysed by increasing the
temperature. If you look up a reation for making a phenol from a diazonium compound and follow that but with your reactants.
Google "reactions of diazonium compounds" and do some reading. Look in the library section of this site (www.sciencemadness.org) specifically look up experiments in Practical Organic Chemistry by A. I. Vogel or take a look on www.orgsyn.org for diazonium reactions.
Research is an important technique to learn, just as important as experimental technique.. try this before you get attacked for incompetence by some
older members of this board! 
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falala
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I've done my research and I know that SA is prepared by common rxns such as oxidation from aglycone and kolbe rxn with phenol. no reference shows
AA--> SA very well, that's why I'm trying to ask.
thanks anyway
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sparkgap
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As to diazotizing anthranilic acid (even though I still think better things can be done with diazotized anthranilic acid), do look at this. Presumably, carefully warming the aqueous solution should give you salicylic acid.
sparky (~_~)
"What's UTFSE? I keep hearing about it, but I can't be arsed to search for the answer..."
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falala
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thanks! 
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panziandi
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Well what I'm saying is you research the GENERAL reaction that converts an aromatic amine to a phenol. You then have your answer!
For example: http://www.orgsyn.org/orgsyn/prep.asp?prep=cv1p0404 details preparation of m-nitrophenol from m-nitroaniline. Follow this procedure but using
anthranilic acid instead of m-nitroaniline and work up the product with an acidification and extraction with diethyl ether etc.
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falala
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right. thanks. someone gave me that link too. thanks again
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Sauron
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I completely agree that salicylic acid is a whole lot easier to come by than anthranilic acid.
So the question ought to be how to make anthranilic acid from salicylic acid and not the other way round.
Sic gorgeamus a los subjectatus nunc.
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chemrox
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Use the AA for something more fun and extract the SA from headache tablets.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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sparkgap
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I'm inclined to think that the "they" alluded to in the third post in this thread must be some academic institution; no one else can be that
impractical. 
sparky (~_~)
"What's UTFSE? I keep hearing about it, but I can't be arsed to search for the answer..."
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Sauron
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It does sound like homework or an open book exam question, doesn't it?
Intermediates in diazotization?
Sophomore, first year of organic course?
Hard for me to judge, I'm 40 years beyond all that, I despair when I am told of how they teach undergrads these days.
Sic gorgeamus a los subjectatus nunc.
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panziandi
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Well I thought it looked like a pre-lab exercise that is why I gave a vague outline and suggested some sources to take a look at for the general
procedure that he could adopt and interpret to this particular and specific example...rather than spoon feeding someone their homework answers.
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sparkgap
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| Quote: | Originally posted by Sauron
I despair when I am told of how they teach undergrads these days. |
You say that; I on the other hand despair of having had to saponify concentrated grape flavoring because #@$&*! company would not sell the acid
without a fair amount of paperwork back in the day (I never did like supposedly needless extra steps). I almost wept at reading his proposal.
sparky (~_~)
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Sauron
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You mean, to get methyl anthranilate?
Anthranilic acid is not that hard to make, from phthalimide, and phthalimide is dead easy to make from phthalic anhydride and urea, or ammonium
hydroxide (conc) or ammonium carbamate.
If I were to do it again I'd judt buy the potassium phthalimide.
Sic gorgeamus a los subjectatus nunc.
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falala
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| Quote: | Originally posted by sparkgap
I'm inclined to think that the "they" alluded to in the third post in this thread must be some academic institution; no one else can be that
impractical.
sparky (~_~) |
yeah it's because i'm in high school.
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falala
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| Quote: | Originally posted by Sauron
It does sound like homework or an open book exam question, doesn't it?
Intermediates in diazotization?
Sophomore, first year of organic course?
Hard for me to judge, I'm 40 years beyond all that, I despair when I am told of how they teach undergrads these days. |
no, no. I'm in my last year of high school. We're supposed to perform this in our lab class next week.
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Sauron
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In what country?
Sic gorgeamus a los subjectatus nunc.
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Nicodem
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Falala, the diazonium zwitterion prepared from anthranilic acid decomposes to benzyne (and this immediately further) on heating: http://sciencemadness.org/talk/viewthread.php?tid=8898
Please, next time use the search engine before posting. Also when opening new threads without providing any references, please do so in the Beginnings
section where I'm moving it anyway.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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