RNMSleep
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Zinc catalysed reduction on 1-Phenyl-2-nitropropene
Hello,
I have done
Reduction of 1-(2,4,5-Trimethoxyphenyl)-2-nitropropane to 2,4,5-Trimethoxyamphetamine
3g (11.7 mmol) 1-(2,4,5-trimethoxyphenyl)-2-nitropropane was dissolved in 20ml MeOH containing 2.5g (38.2 mmol) zinc powder (activated by stirring in
20ml 5% aq. HCl for two minutes then washed with 3x50ml water and finally 20ml MeOH). To the stirred mixture 1.9g (30 mmol) ammonium formate was added
in one portion. The mixture became warm to the touch within one minute. After 15 minutes the mixture was filtered to remove the residual zinc and the
solvent removed by distillation. The residual oil was dissolved in 25ml EtOAc and neutralized with dry HCl in IPA. The solution was heated to 60C and
vacuum applied to remove about 10ml EtOAc. The residual solution was slowly cooled to room temp and the walls of the flask scratched with a glass rod.
Crystals begun to grow very quickly and within 1 minute the solution was a thick slurry. The crystals was isolated by filtration, washed with 50ml
acetone and dried to constant weight.
Yield: 2.1 grams (8.0 mmol, 68%) of 2,4,5-Trimethoxyamphetamine Hydrochloride (TMA-2HCl)
Does it works with every nitrostyrene or nitropropene?
I have done it too with unsubstituted P2np but i wasnt able to get any amphetaminesulfate. does someone know this reaction and can give me some more
information. greetz RNM
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manimal
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The former compound was a saturated nitropropane, correct? Zn/HCl will reduce a nitro group but not a double bond, so when applied to a nitropropene
the unaturated amine will rearrange to an imine and then to a ketone.
To reduce it to an amine, you need a more energetic reducing agent, or a stepwise reduction with NaBH4 to reduce the double bond followed by Zn/HCl,
or electroreduction.
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kclo4
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A clemmensen reduction would also work, correct?
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DJF90
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A Clemmensen reduction is boiling with HCl/Zn, but is generally a rather violent reaction and is generally used to remove a ketone group when no other
functionalities are present in the molecule.
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kclo4
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boiling with HCl/Zn? Why does it need to be boiling?
I thought it used a zinc amalgam and some how that makes it reduce more effectively then just HCl/Zn.
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Polverone
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This isn't really the right site for this question.
PGP Key and corresponding e-mail address
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