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Topic: 2-methylpyridine-n-oxide synthesis  (Read 6518 times)

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Offline guilun_001

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2-methylpyridine-n-oxide synthesis
« on: March 15, 2009, 07:29:52 AM »
  The  reaction is oxidation of  2-methylpyridine to make the 2-methylpyridine-n-oxide. I use the mixture of acetic acid/H2O2 ,
The real problem is the isolation/purification part. I go with steamed decompression acid,Put the solution to neutralization with  NaHCO3,And chloroform extract ,The organic phase vacuum distillation,Cooling,But the product does not precipitate,How do?

Offline sjb

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Re: 2-methylpyridine-n-oxide synthesis
« Reply #1 on: March 15, 2009, 01:25:42 PM »
From what I can remember, pyridine-N-oxides are fairly polar and water soluble. Have you checked your aqueous phase to see if there's any left in there?

Offline AWK

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Re: 2-methylpyridine-n-oxide synthesis
« Reply #2 on: March 16, 2009, 03:15:20 AM »
mp 48-50 C. It is hygroscopic. It should be extremely pure to solidify.
AWK

Offline challakrishna76

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Re: 2-methylpyridine-n-oxide synthesis
« Reply #3 on: April 01, 2009, 01:41:05 AM »
1.if you are not bothered abt yield try the reaction in MCPBA/DCM at below RT

2. if u try your method in H2O2 then pyridine n oxides are water soluble and your aq layer should be basified with 50 % aq NaOH then give extractions

what from my earlier exp method 1 is good

good luck,

challakrishna@rediffmail.com

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