I think the only shortcoming of this video is that it doesn't split the ephedrine because what you get is mixed ephedrine. I think no one in our forum is willing to split ephedrine and share the video. If someone does, he is a great chemist.
I think the only shortcoming of this video is that it doesn't split the ephedrine because what you get is mixed ephedrine. I think no one in our forum is willing to split ephedrine and share the video. If someone does, he is a great chemist.
Guys plant derived Ephedrine and PseudoEphedrine possess a D rotatory alpha carbon.
During our beloved reduction reaction the only variating chiral center is the beta one (losing the 4th substituent, the hydroxyl, to an Hydrogen, implies the disappearance of the chirality of carbon beta in M-AMP.
Why? Simply because instead of R'-CH-OH-R" (Eph/PseudoEph) it will just become a R'-CH2-R".
So in simpler terms the chirality of the beta carbon doesn't matter because the hydroxyl (-OH) found in Eph/PseudoEph is cleaved to yield enantiopure D-MethylAMP regardless.
Different story is when you build methylAmp from symmetric precursors (see the P2P, CH3NH2,... route).
So NO, ephedrine is not "mixed" unless you synthesize it rather than extracting from a plant matrix such as ephedra sinica since nature usually function with enantiomerically pure structures. A clear example is the one of aminoacids: all the nature ones are L-AA--> L-Arginine, L-Methionine, L-Tyrosine, L-Tryptophan,...
The only situation where you will get a racemix mixture is when you start from phenylacetone as main precursor (P2P) which also is the only situation where 2-3 Tartaric Acid optical resolutions makes sense (and would be desired) to pass from a D:L of around 50:50 sequentially to: