
Glad somebody likes the idea.
I read several papers that detailed the synthesis, but I don't have them, I'll have to find them again. If I remember correctly the first step is to hydrolyze off the acetate group of the salv-A to produce salvinorin-B. Not a hard step. The second step is to react it with methoxymethyl chloride (also known as chloromethyl methyl ether) which is not OTC but can be synthesized with a bit of effort (via dimethoxymethane and benzoyl chloride which can both be synthed from OTC materials IIRC). The yields on both steps are pretty good too.
The isolation of salv-A from leaves is pretty simple. Pretty much consists of extracting with cold acetone, boiling off the acetone, washing the residue with toluene/naptha, recrystalizing from methanol and if you want, dissolving it and running it through a column of activated carbon. That should give a pure product and is basically the method used by university researchers. Yield is around 1g per pound of dry leaf. If it's 7 times the potency of salv-A, 1g would go a long way!
I too would love to try this stuff at least once, even if it was not a fun trip.
EDIT:
OK I found it:
Synthesis of Salvinorin-B:
"To a cold (0° C.) solution of salvinorin-A (153.0 mg, 0.35 mmol) in MeOH (3 mL) and CH2Cl2 (3 mL) was added K2CO3 (98 mg, 0.71 mmol) and the mixture was stirred at 0° C. (20 minutes). Water (5 mL) and CH2Cl2 (5 mL) were added to the reaction mixture. The organic layer was concentrated in vacuo and then purified by column chromatography (SiO2 ; 4:1, CH2Cl2 :EtOAc) to obtain 66 mg (48%) of pure Salv-B as a white solid.
Synthesis of 2-methoxymethyl-salvinorin-B:
"10 mg of Salvinorin-B was dissolved in 5 mL of anhydrous CH2Cl2 to which was added a catalytic amount of dimethylaminopyridine (1 mg), N,N-Diisopropylethylamine (2 eq) and methoxymethyl chloride (2 eq) at room temperature and the reaction was stirred for 48 hours. After completion of the reaction, water was added (10 mL) to the reaction mixture followed by extraction with EtOAc (2×10 mL). The organic layer was dried (Na 2 SO 4 ) and concentrated to afford a crude mixture. The crude mixture was further purified by column chromatography (1:2, EtOAc:Hexane) to give the pure compound"
I had forgot about needing the catalytic dimethylaminopyridine and N,N-Diisopropylethylamine. That does make things a little harder.. Still these compounds are certainly not insurmountable, and an alternative route may be possible.