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Topic: Pruification of amines  (Read 2890 times)

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Offline prachiti

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Pruification of amines
« on: March 10, 2017, 11:39:48 PM »
I am to purify 4-isopropyl amine of its coloured impurities. Vacuum distillation is not feasible because we do not have a strong vacuum pump (M.P.- 183 degree centigrade). Should i try activated charcoal? If not, then what other methods can i apply?

Offline sjb

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Re: Pruification of amines
« Reply #1 on: March 11, 2017, 04:52:37 AM »
On what sort of scale? Chromatography? Recrystallisation as a salt?

What is the actual compound (the name seems missing something)

Offline prachiti

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Re: Pruification of amines
« Reply #2 on: March 11, 2017, 10:00:43 AM »
A chromatographic scale is what i was looking for since i have less amount of compound available.

The compound goes by 4-isopropyl aniline (attaching an image). Regarding the impurities, they are coloured and four in number apart from the amine (with a TLC reference), I tried out purification by activated charcoal. It however, didn't turn out as i expected.

Purification by salt formation didn't work as expected and showed same TLC results before treating the sample.

Offline sjb

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Re: Pruification of amines
« Reply #3 on: March 16, 2017, 08:44:10 AM »
Do you have any idea what your contaminants might be? Try e.g. TLC in various EtOAc/hexanes mixtures to see if you get separation that way.

Offline hypervalent_iodine

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Re: Pruification of amines
« Reply #4 on: March 16, 2017, 09:35:01 AM »
Do you have any idea what your contaminants might be? Try e.g. TLC in various EtOAc/hexanes mixtures to see if you get separation that way.

DCM / MeOH tends to be better for amines in my experience. Column chromatography of this should be fairly straightforward.

Offline prachiti

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Re: Pruification of amines
« Reply #5 on: March 17, 2017, 06:18:48 AM »
I am onto a CHCl3 column and it is running well. I am getting my amine in pure form.
A TLC shows in total 4 components. I am assuming one of the contaminants is an N-oxide. The others i am clueless about. 
Thank you!

Offline hypervalent_iodine

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Re: Pruification of amines
« Reply #6 on: March 17, 2017, 07:43:10 AM »
Could you give some more detail on the exact reaction you're doing?

Offline organic92

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Re: Pruification of amines
« Reply #7 on: April 15, 2017, 06:39:05 PM »
Do the hydrocloride ( by treatment with HCL:Et2O) and then NaOH washing.

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