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OK Extraction done .

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Radiumhero:
Well i extracted the P2P and i have to say that the yield is not as bad as exspected ~ 24 ml P2P. And I used 63 ml Benzylchlorid and little more than 38 ml Acetonitril. But my P2P is really dark ! dark brown colored , with a really lets call it unpleasant smell , ( little bit like some sort of plant but this must be an ugly one ...)

Bandil:
How did you extract it and verify that it is P2P?

In my experience with this method, you get something from the distillation, with a b.p. not too far for that of P2P (cant remember the exact b.p., lost the notes). It is however NOT p2p...

Regards
Bandil

Radiumhero:
Well started with acidifation of this funny white salt  followed by 3 times extraction with 35 ml Et2O( NaCl has been added to mixture .) to remove the yellow color from the bottom (water ) Layer. Et2O extracts pooled together and washed with Water .
Water removed by Dropping funnel and heatng to 110 C. Well ill make a sample with anilin acrylation and compare Products by chromatography. by the way ( wich solvent dont know the english word for it // Fließmittel // works best ?)
And i also looked at the pics by xicori (Meerwein acrylisation...) and his crude >Keton looks exactly like mine !! the only Problem is my Vakuumpump broke . ( u can still turn it on but it makes really unpleasant sounds like sth is scraping insinde ...) Can i destill it without too much loss @ atmospheric pressure ?

moo:
The problem isn't excactly the reactivity of the nitrile. One major problem is the fact that the nitrile is acidic enough to protonate the Grignard reagent, turning your precious benzylmagnesium chloride to plain toluene. The deprotonated acetonitrile then goes on and forms different side reaction products. I have a reference to back this up somewhere. Of course one can argue that it is about reactivity because if the reaction with the nitrile was much faster than a proton transfer, this problem would not exist. But proton transfers are known to be very fast reactions.

I think that another problem is the addition of a second molecule of the Grignard reagent to the formed salt of the imine (iminate?), the reason why Grignard reagent should be added to an excess of the nitrile and not the other way around.

However, the reaction is proven to give P2P in literature several times, yields are the problem.

Novice:
If the problem is deprotonation of acetonitril, then the exact same reaction but instead of hydrolysis with acid, reduction with NaBH4 to amphetamine is consulted should not give an 80% yield1. Am I wrong in my reasoning? As the reduction step comes post-imin formation...

1 JACS 109, 3378-3387 (1987) Procedure adapted from the synthesis of #49 (https://www.thevespiary.org/rhodium/Rhodium/chemistry/amphetamine.html)

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