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                      Revolutionary 2-CH success - by KrZ
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This spectacularly successful new method comes to us from J. Org. Chem. 1982,
47, p. 2638-2643.  In this article the authors first attempted to produce
2-methoxy-PEA from the nitrostyrene, however, when they attempted to scale-up
this reaction they encountered a number of persistent bugs, in their own words
the reaction was "fickle" when scaled up.  Although nitrostyrene synthesis is
relatively easy, it's reluctance to dissolve in a useful hydrogenation solvent
has led to many problems.  Using GAA and H2SO4 as a dimer inhibitor is the
prefered method, but yields are still not as spectacular as one might hope, and
it takes 2L of GAA to dissolve just 100g of nitrostyrene.

For these reasons we have arrived at the present method, a relatively easy, very
high yielding, and very scalabe reaction for the production of 2CH and Mescaline.  
So let's get started.

Reagents;
2,5-Dimethoxybenzaldehyde
KCN
Ethyl Chloroformate
THF
Palladium on carbon, any percentage available
Anhydrous EtOH

Procedure;

250g of 2,5-Dimethoxybenzaldehyde [1.5 mol] is dissolved in 600ml of THF, 162 g
of Ethyl Chloroformate [1.5 mol] is added and the solution is stirred in an ice
bath until cool. 98g of KCN dissolved in 250ml of water is added all at once,
the mixture is kept at 0C for 8hrs.  After this period of time the ice is
allowed to melt, and the reaction is allowed to warm up to room temperature for
an additional 10hrs.  Upon completion, 1500ml of water is added, and the mixture
is extracted 3x with 125ml of DCM.  The combined DCM extracts are dried with
sodium sulfate, filtered, and the residue is distilled under heavy vacuum to
afford 356.8g of the mandelonitrile as an pale yellow, creamy, thick liquid [bp.
115-120 @ 0.3 mmHg], yield 83.5%.

The entire mass of mandelonitrile is dissolved in 2L of EtOH containing 175g of
H2SO4 and 20g of 10% Pd/C are added.  Eiter a high-pressure hydrogenation or an
atmospheric pressure hydrogenation.  The only difference between the two will be
the reaction time, at 80psi 100% absorption occurs after 90 minutes, at
atmospheric, a 90% yield will be obtained by bubbling the EtOH with a stream of
H2 for a period of 8 hours [Or use a balloon, but don't pull a beaker].  When
the hydrogenation is complete the reaction mix is filtered to recover the Pd/C
which can be washed with additional MeOH and reused several times.  The filtrate
is the cooled on an ice bath and 71.5g of NaOH is slowly added with stirring,
upon completion, if done slowly enough, the mixture will still be cool.  As the
NaOH is added you will not the precipitation of a large mass of Sodium Sulfate,
when done, allow the mixture to stir on the ice bath for another 30 minutes to
assure complete precipitation of the Sodium Sulfate.  The sodium sulfate is
filtered off, and the reaction mix goes directly to distillation where 205.88g
of 2CH will be recover, a 90% yield.

Additional Notes;

If doing a high-psi hydrogenation, the solvent quantity can be cut in half, and
possibly more, making this reaction immensely versatile.  When applied to
3,4,5-trimethoxybenzaldehyde, the yield of mandelonitrile will be cut to ~80%.

I hope this will satisfy those people who have gotten on my case before,
claiming that my write-ups use nothing but high-psi techniques.

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Alphabeta121:
    
A while back during the discussion of Krz's KCN ethylchloroformate reaction to 
make 2-CH, people wanted one with easier to get reagents. Another person 
mentioned the reaction of KCN with the bisulfite addition product of 
2,5-Dimethoxybenzaldehyde and NaHSO3. Well I did some digging and found this 
gold mine in a german reference.  I don't speak german, but here is the 
translation anyway, If any german speaking bee's would be willing to translate 
the paragraph PM me and I'll email you a jpg of the page.

Methoxy-substituted Mandelonitriles from their corresponding Benzaldehydes:

To a solution of 40g NaHSO3 (sodium bisulfite) in 360ml water heated to 40°C, 
44 g 4-Methoxybenzaldehyde (0.324 mol) is added with vigorous stirring. 
After 20 min, cool the reaction mixture down to 0°C, add 200 mL diethyl ether 
and add a solution of 17 g NaCN in 70 mL water dropwise. Let stir for 30 min at 
0°C, separate the organic phase and extract the aqueous phase twice with 50 mL 
portions of ether. The combined ether extracts are then dried over anhydrous 
calcium chloride. After the evaporation of the solvent under a vacuum at 35-40°C, 
the remaining oil is cooled and allowed to solidify. The entire mass of crystals 
is sucked dry on a buchner funnel and is pure enough for hydrogenation.

Looks good eh?  Now just slap this in a Hydrogenation flask with Pd/C, EtOH 
and H2SO4, and blammo, enough 2-CH to kill a horse.

Important:  My question is, will the mandelonitrile reduce to the PEA w/ Pd/C 
at 1 atm pressure or will it reduce to the amino alcohol. At higher pressure 
I'm certain that the benzylic alcohol would be removed, but at one atm I'm 
not so sure.  Krz's mandelonitrile route doesn't actually synth the 
mandelonitrile, it synthesizes the O-ethoxycarbonyl ester, which would be much 
easier to reduce IMHO. 

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