Asymbescaline · 3,4-Diethoxy-5-methoxyphenethylamine
#9 ASB SYNTHESIS: To a solution of 32 g of 5-bromobourbonal in 150 mL DMF there was added 31 g ethyl iodide and 32 g of finely ground 85% KOH pellets. There was the formation of a purple color and a heavy precipitate. On gradual heating to reflux, the color faded to a pale yellow and the precipitate dissolved over the course of 1 h. The heating was continued for an additional 1 h. The reaction mixture was added to 1 L H2O, and extracted with 2×150 mL of petroleum ether. The extracts were pooled, washed with 2×200 mL 5% NaOH and finally with H2O. After drying over anhydrous K2CO3 the solvents were removed under vacuum to yield 36 g of crude 3-bromo-4,5-diethoxybenzaldehyde as an amber liquid. This was used without purification for the following step. Distillation at 105–115 °C at 0.3 mm/Hg provided a white sample which did not crystallize. Anal. (C11H13BrO3 ) C,H.
A mixture of 36 g 3-bromo-4,5-diethoxybenzaldehyde and 17 mL cyclohexylamine was heated with an open flame until it appeared to be free of H2O. The residue was put under a vacuum (0.4 mm/Hg) and distilled at 135–145 °C, yielding 42 g 3-bromo-N-cyclohexyl-4,5-diethoxybenzylidenimine as a viscous light greenish oil. This slowly set to a crystalline glass with a mp of 60–61 °C. Recrystallization from hexane gave a white crystalline product without any improvement in the mp. Anal. (C17H24BrNO2) C,H. This is a chemical intermediate to a number of active bases, taking advantage of the available bromine atom. This can be exchanged with a sulfur atom (leading to and ) or with an oxygen atom as described below.
A solution of 18 g 3-bromo-N-cyclohexyl-4,5-diethoxybenzylidenimine in 250 mL anhydrous Et2O was placed in an atmosphere of He, stirred magnetically, and cooled with an external dry ice/acetone bath. Then 36 mL of a 1.5 M solution of butyllithium in hexane was added over 2 min, producing a clear yellow solution. This was stirred for 10 min. There was then added 30 mL of butyl borate at one time, the stirring continued for 5 min. The stirred solution was allowed to return to room temperature. There was added 150 mL of saturated aqueous ammonium sulfate. The Et2O layer was separated, and the aqueous phase extracted with another 75 mL Et2O. The combined organic phases were evaporated under vacuum. The residue was dissolved in 100 mL MeOH, diluted with 20 mL H2O, and then treated with 15 mL 35% H2O2 added over the course of 2 min. This mildly exothermic reaction was allowed to stir for 15 min, then added to 500 mL H2O. This was extracted with 2×100 mL CH2Cl2 and the solvent removed under vacuum. The residue was suspended in 150 mL dilute HCl and heated on the steam bath for 0.5 h. Stirring was continued until the reaction was again at room temperature, then it was extracted with 2×75 mL CH2Cl2. These extracts were pooled and extracted with 3×100 mL dilute aqueous KOH. The aqueous extracts were washed with CH2Cl2, reacidified with HCl, and reextracted with 2×75 mL CH2Cl2. These extracts were pooled, and the solvent removed under vacuum to yield a brown residue. This was distilled at 107–127 °C at 0.4 mm/Hg to yield 8.3 g of 3,4-diethoxy-5-hydroxybenzaldehyde as an oil that set to a tan solid. Recrystallization from cyclohexane gave a white product with a mp of 70.5–71.5 °C. Anal. (C11H14O4) C,H.
A solution of 8.3 g of 3,4-diethoxy-5-hydroxybenzaldehyde and 3.0 g KOH in 75 mL EtOH was treated with 5 mL methyl iodide and stirred at room temperature for 5 days. The reaction mixture was added to 400 mL H2O and extracted with 2×50 mL CH2Cl2. The extracts were pooled, washed with 2×150 mL dilute NaOH, and the solvent removed under vacuum. The residual oil was distilled at 95–110 °C at 0.3 mm/Hg to yield 8.2 g of 3,4-diethoxy-5-methoxybenzaldehyde as a pale yellow liquid. This product was a crystalline solid below 20 °C but melted upon coming to room temperature. It was analyzed, and used in further reactions as an oil. Anal. (C12H16O4) C,H.
To a solution of 6.4 g 3,4-diethoxy-5-methoxybenzaldehyde in 40 mL nitromethane there was added about 0.5 g anhydrous ammonium acetate, and this was held at reflux for 1 h. The excess solvent/reagent was removed under vacuum, producing a red oil which set up to crystals. These were recrystallized from 40 mL boiling MeOH to yield 3.0 g of 3,4-diethoxy-5-methoxy-β-nitrostyrene as yellow plates, with a mp of 89–90 °C. Anal. (C13H17NO5) C,H.
A solution of 3.0 g LAH in 150 mL anhydrous THF under He was cooled to 0 °C and vigorously stirred. There was added, dropwise, 2.1 mL of 100% H2SO4, followed by the dropwise addition of a solution of 3.5 g 3,4-diethoxy-5-methoxy-β-nitrostyrene in 30 mL anhydrous THF, over the course of 10 min. The addition was exothermic. The mixture was held at reflux on the steam bath for 30 min. After cooling again, the excess hydride was destroyed with IPA, followed by the addition of 10% NaOH sufficient to covert the aluminum oxide to a white, granular form. This was removed by filtration, the filter cake washed with IPA, the mother liquor and filtrates combined, and the solvents removed under vacuum to provide a yellow oil. This residue was added to 100 mL dilute H2SO4 producing a cloudy suspension and some yellow insoluble gum. This was washed with 2×75 mL CH2Cl2. The aqueous phase was made basic with 25% NaOH, and extracted with 2×75 mL CH2Cl2. The solvent was removed from these pooled extracts and the residue distilled at 110–135 °C at 0.4 mm/Hg to provide 2.0 g of a colorless liquid. This was dissolved in 7 mL IPA, neutralized with about 40 drops of concentrated HCl, followed by 50 mL anhydrous Et2O with stirring. The initially clear solution spontaneously deposited a white crystalline solid. This was diluted with an additional 30 mL Et2O, let stand for 1 h, and the solids removed by filtration. After Et2O washing, the product was air-dried to yield 1.25 g of 3,4-diethoxy-5-methoxyphenethylamine hydrochloride (ASB) with a mp of 142–143 °C. Anal. (C13H22ClNO3) C,H.
DOSAGE: 200–280 mg.
DURATION: 10–15 h.
QUALITATIVE COMMENTS: (with 240 mg) “There was a pleasant and easy flow of day-dreaming thoughts, quite friendly and somewhat erotic. There was a gentle down-drift to my starting baseline mental status by about midnight (I started at 9:00 a.m.). I never quite made it to a +++, and rather regretted it.”
(with 280 mg) “The plateau of effect was evident by hour two, but I found the experience lacking the visual and interpretive richness that I had hoped for. Sleep was very fitful after the effects had largely dropped—it was hard to simply lie back and relax my guard—and even while being up and about the next day I felt a residual plus one. Over all, there were few if any of the open interactions of or . Some negative side seemed to be present.”
(with 280 mg) “The entire session was, in a sort of way, like being in a corridor outside the lighted halls where a beautiful experience is taking place, sensing the light from behind a grey door, and not being able to find my way in from the dusky underside passageways. This is sort of a gentle sister of , but with a tendency to emphasize (for me, at this time) the negative, the sad, the struggling. Sleep was impossible before the fifteenth hour. When I tried, I got visions of moonlight in the desert, with figures around me which were the vampire-werewolf aspect of the soul, green colored and evil. I had to sit quietly in the living room and wait patiently until they settled back to wherever they belonged and stopped trying to take over the scene. During the peak of the experience, my pulse was thready, somewhat slowed, and uneven. There was a faint feeling of physical weirdness.”
EXTENSIONS AND COMMENTARY: This specific amine was a target for a single study in cats many years ago, in Holland, using material obtained from Hoffman La Roche in Basel. Their findings are hard to evaluate, in that 200 milligrams was injected into a 3.75 kilogram cat (53 mg/kg), or about twice the dosage that they used in their studies with . Within 5 minutes there were indications of catatonia, and within a half hour the animal was unable to walk. This condition persisted for two days, at which time the animal died. Although this dose was many times that used in man, perhaps hints of the physical unease and long action are there to be gleaned. The consensus from over a half dozen experiments is that there is not enough value to be had to offset the body load experienced.
A comment is needed on the strange name asymbescaline! In the marvelous world of chemical nomenclature, bi- (or di-) usually means two of something, and tri- and tetra- quite reasonably mean three and four of something. But occasionally there can be an ambiguity with bi (or tri or tetra) in that bi something-or-other might be two something-or-others hooked together or it might be two things hooked onto a something-or-other. So, the former is called bi- and the latter is called bis-. This compound is not two escalines hooked together (bi-escaline) but is only one of them with two ethyl groups attached (bis-escaline or bescaline). And since there are two ways that this can be done (either symmetrically or asymmetrically) the symmetric one is called (or for short) and this one is called asymbescaline (or ASB for short). To complete the terminology lecture, the term tri- becomes tris- (the name given for the drug with all three ethoxy groups present in place of the methoxys of ) and the term tetra- mutates into the rather incredible tetrakis-!
13 May 2016 · Creative Commons BY-NC-SA ·

About PiHKAL · info

This version of Book II of PiHKAL is based on the Erowid online version, originally transcribed by Simson Garfinkle and converted into HTML by Lamont Granquist. I drew also on “Tyrone Slothrop’s” (Unfinished) Review of PIHKAL to enumerate the many analogues mentioned in PiHKAL but not described at length. Many, many others have since been added.
I have tried here to expunge any artifacts introduced by the earlier transcriptions and restore the typographic niceties found in the printed edition. I’ve also made minor changes to some chemical names in line with current nomenclature practice. Typically the change is little more than expanding a prefix or setting it in italics. The history page has further details.

Cautionary note

“At the present time, restrictive laws are in force in the United States and it is very difficult for researchers to abide by the regulations which govern efforts to obtain legal approval to do work with these compounds in human beings.
“No one who is lacking legal authorization should attempt the synthesis of any of the compounds described in these files, with the intent to give them to man. To do so is to risk legal action which might lead to the tragic ruination of a life. It should also be noted that any person anywhere who experiments on himself, or on another human being, with any of the drugs described herein, without being familiar with that drug’s action and aware of the physical and/or mental disturbance or harm it might cause, is acting irresponsibly and immorally, whether or not he is doing so within the bounds of the law.”
Alexander T. Shulgin

Copyright notice

The copyright for Book I of PiHKAL has been reserved in all forms and it may not be distributed. Book II of PiHKAL may be distributed for non-commercial reproduction provided that the introductory information, copyright notice, cautionary notice and ordering information remain attached.

Ordering information

PiHKAL is the extraordinary record of the authors’ years exploring the chemistry and transformational power of phenethylamines. This book belongs in the library of anyone seeking a rational, enlightened and candid perspective on psychedelic drugs.
Though Sasha and Ann have put Book II of PiHKAL in the public domain, available to anyone, I strongly encourage you to buy a copy. We owe them — and there’s still nothing quite like holding a real book in your hands.
PiHKAL (ISBN 0-9630096-0-5) is available for US$24.50 (plus $10 domestic first-class shipping) from Transform Press.
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