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Book II of PiHKAL: A Chemical Love Story, by Alexander & Ann Shulgin #26: 2C-F
#26 2C-F: 2,5-Dimethoxy-4-fluorophenethylamine

#26 2C-F SYNTHESIS: A solution of 76.6 g 2,5-dimethoxyaniline in 210 mL H2O containing 205 mL fluoroboric acid was cooled to 0 °C. with an external ice bath. There was then added, slowly, a solution of 35 g sodium nitrite in 70 mL H2O. After an additional 0.5 h stirring, the precipitated solids were removed by filtration, washed first with cold H2O, then with MeOH and finally Et2O. Air drying yielded about 100 g of the fluoroborate salt of the aniline as dark purple-brown solids. This salt was pyrolyzed with the cautious application of a flame, with the needed attention paid to both an explosion risk, and the evolution of the very corrosive boron trifluoride. The liquid that accumulated in the receiver was distilled at about 120 °C at 20 mm/Hg, and was subsequently washed with dilute NaOH to remove dissolved boron trifluoride. The product, 2,5-dimethoxyfluorobenzene, was a fluid, straw-colored oil that weighed 7.0 g.

To a vigorously stirred solution of 40.7 g 2,5-dimethoxyfluorobenzene in 215 mL CH2Cl2 cooled with an external ice bath, there was added 135 g of anhydrous stannic chloride. There was then added, dropwise, 26 g of dichloromethyl methyl ether at a rate that precluded excessive heating. The reaction mixture was allowed to come to room temperature over the course of 0.5 h, and then quenched by dumping into 500 g shaved ice containing 75 mL concentrated HCl. This mixture was stirred for an additional 1.5 h. The separated organic layer was washed with 2×100 mL dilute HCl, then with dilute NaOH, then with H2O and finally with saturated brine. Removal of the solvent under vacuum yielded a solid residue that was recrystallized from aqueous EtOH yielding 41.8 g 2,5-dimethoxy-4-fluorobenzaldehyde with a mp of 99–100 °C.

A solution of 2.5 g 2,5-dimethoxy-4-fluorobenzaldehyde in 15 mL acetic acid containing 1 g nitromethane was treated with 0.2 g anhydrous ammonium acetate, and heated on the steam bath for 4 h. After cooling, and following the judicious addition of H2O, crystals separated, and additional H2O was added with good stirring until the first signs of oiling out appeared. The solids were removed by filtration, and recrystallized from acetone to give 2.0 g of 2,5-dimethoxy-4-fluoro-β-nitrostyrene with a mp of 159–162 °C.

To a suspension of 2.0 g LAH in 200 mL cool anhydrous Et2O under an inert atmosphere, there was added a THF solution of 2.0 g 2,5-dimethoxy-4-fluoro-β-nitrostyrene. The reaction mixture was stirred at room temperature for 2 h and then heated briefly at reflux. After cooling, the excess hydride was destroyed by the cautious addition of H2O, and when the reaction was finally quiet, there was added 2 mL of 15% NaOH, followed by another 6 mL of H2O. The basic insolubles were removed by filtration, and washed with THF. The combined filtrate and washes were stripped of solvent, yielding a residual oil that was taken up in 10 mL of IPA, neutralized with concentrated HCl, and the generated solids diluted with anhydrous Et2O. The white crystalline 2,5-dimethoxy-4-fluorophenethylamine hydrochloride (2C-F) was recrystallized from IPA to give an air-dried product of 0.5 g with a mp of 182–185 °C.

DOSAGE: greater than 250 mg.

DURATION: unknown

QUALITATIVE COMMENTS: (with 250 mg) “Even at 250 milligrams, the effects were slight and uncertain. There may have been some eyes-closed imagery above normal, but certainly not profound. At several hours there was a pleasant lethargy; sleep was completely normal that night.”

EXTENSIONS AND COMMENTARY: A number of graded acute dosages were tried, and it was only with amounts in excess of 100 milligrams that there were any baseline disturbances at all. And at no dose that was tried was there any convincing indication of believable central effects.

The three-carbon amphetamine analogue of 2C-F would quite logically be called DOF (2,5-dimethoxy-4-fluoroamphetamine). It has been prepared by reaction of the above benzaldehyde with nitroethane (giving 1-(2,5-dimethoxy-4-fluorophenyl)-2-nitropropene, with a melting point of 128–129 °C from ethanol) followed by LAH reduction to DOF (the hydrochloride salt has a melting point of 166–167 °C, after recrystallization from ether/ethyl acetate/ethanol). Animal studies that have compared DOF to the highly potent DOI and DOB imply that the human activity will be some four to six times less than these two heavier halide analogues. As of the present time, no human trials of DOF have been made.

Page updated 30 March 2012 · This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License ·

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. Still others remain to be added.

I have tried here to expunge any artifacts introduced by the earlier transcriptions and restore most of the typographic niceties found in the printed edition. I’ve also made minor changes to some chemical names in line with current nomenclature practice, and in the hope of aligning with more readers’ searches. Typically the change is little more than expanding a prefix and setting it in italics. The errata and changes 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.

Although 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.

Transform Press,
Box 13675
Berkeley, CA 94701

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