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Topic: Why codeine not soluble in NaOH(aq) eventhough it has OH?  (Read 9070 times)

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Offline ahfei

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Why codeine not soluble in NaOH(aq) eventhough it has OH?
« on: November 30, 2007, 06:39:56 AM »
Why codeine not soluble in NaOH(aq) eventhough it has OH?
http://en.wikipedia.org/wiki/Codeine

And what happen to OH and amine group of morphine in acidic and alkaline solution?
http://en.wikipedia.org/wiki/Morphine

I'm new here so hi ;) Going to be a frequent visiter here since pharmacy involve lots of chemistry :D

I post the link to structure pic. I believe it's just normal chemistry principle.
« Last Edit: November 30, 2007, 07:01:38 AM by ahfei »

Offline AWK

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #1 on: November 30, 2007, 07:42:01 AM »
Codeine has no acidic group - it is worse soluble in NaOH than in water
The second molecule have both: acidic and basic groups
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Offline ahfei

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #2 on: December 04, 2007, 10:22:20 AM »
emmm, still not a clear pic for me.

Offline AWK

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #3 on: December 04, 2007, 11:05:38 AM »
Acidic property shows phenolic OH group, codeine bears only an alcoholic OH group! MOrphine has both: phenolic and alcoholic OH groups.
« Last Edit: December 04, 2007, 11:22:17 AM by AWK »
AWK

Offline ahfei

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #4 on: December 04, 2007, 01:19:32 PM »
Thanks. AWK (what does that means?)

now i get it. Do you by chance know why morphine does not react with methylating agent like Me2SO4 without NaOH?

Offline AWK

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #5 on: December 05, 2007, 01:02:50 AM »
Draw the mechanism of methylation!
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Offline lutesium

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #6 on: December 15, 2007, 02:12:29 AM »
Its not releated with the -OH group! Amines aren't soluble in basic water solutions. And nohting happens to -OH groups or somewhere else of the amines in basic or acidic solutions!!!


Lutesium...

Offline AWK

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #7 on: December 16, 2007, 05:20:48 AM »
Its not releated with the -OH group! Amines aren't soluble in basic water solutions. And nohting happens to -OH groups or somewhere else of the amines in basic or acidic solutions!!!


Lutesium...
phenolic OH reacts with bases! Tere is a standard test for detecting phenolic OH with such base as Na2CO3
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Offline lutesium

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #8 on: December 16, 2007, 09:59:49 PM »
But I were talking about solubility!!! Of course phenolic -OH groups change to a -ONa+ but this change is not permenant!


Lutesium...

Offline AWK

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #9 on: December 17, 2007, 01:05:53 AM »
But I were talking about solubility!!! Of course phenolic -OH groups change to a -ONa+ but this change is not permenant!


Lutesium...

As far as we are talking about solubility in pure solvent , you are right.
But bases and acids react in acidic or basis conditions, respectively. Then we are talking about solubility of other compounds.
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Offline lutesium

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Re: Why codeine not soluble in NaOH(aq) eventhough it has OH?
« Reply #10 on: December 17, 2007, 05:50:12 AM »
The only change that I know (which is permanent) is refluxing these two substance with HI causes the rupture of the O bridge of these compounds affording Apomorphine (A D2 Dopamine agonist) as far as I know the other conditions don't effect these two amines and NO amine can dissolve in aquaeous NaOH solutions (I'm sure about this 'cuz its a fact)!!!


Lutesium...

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