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Topic: Porphyrin help HNMR  (Read 3833 times)

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Offline Mocook

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Porphyrin help HNMR
« on: October 27, 2013, 11:49:21 PM »
Hello,
I recently ran a reaction and attempted to isolate a porphyrin sample via flash column than recrystallization and attained a NMR with the following but I'm unsure if the sample is still a mixture of porphyrins. Can anyone enlighten me please because I'm trying to characterize any product but this seems like a mixture to me.

Offline Mocook

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Re: Porphyrin help HNMR
« Reply #1 on: October 27, 2013, 11:50:42 PM »
This as well

Offline Dan

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Re: Porphyrin help HNMR
« Reply #2 on: October 28, 2013, 04:03:12 AM »
I recently ran a reaction and attempted to isolate a porphyrin sample

Please give details. Starting material? Reaction conditions? Proposed product?
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Offline Mocook

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Re: Porphyrin help HNMR
« Reply #3 on: October 28, 2013, 10:47:29 AM »
I totally forgot to include that stuff!

But the reactant is meso-tetra(4-methylphenyl) porphine.

The reaction is a bromination reaction. 
    Successful bromination- confirmed by Beilstein test.
 
Initially the reaction was expected to yield a bromine on the methyl positions but the NMR does not indicate a signal at 4.4ppm which is the signal needed based in other sources.

I believe the bromine attacked the pyrrole positions or directly on the phenyl based on the HNMR.

Chloroform NMR solvent

Offline Corribus

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Re: Porphyrin help HNMR
« Reply #4 on: October 28, 2013, 12:05:09 PM »
Looks like a mixture. Beta protons are a mess of peaks.  So either you have a mixture or you got bromination at one or more of the beta positions. 
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

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