Pihkal

by Alexander Shulgin

  CH2Cl2. The extracts were pooled, washed with 5% NaOH, and the solvent removed under vacuum yielding 8.8 g of a yellow oil, undoubtedly containing propyl iodide. This residue was distilled at 133-145 !C at 0.15 mm/Hg to yield 4.5 g of 3,4-dimethoxy-5-(n)-propoxybenzaldehyde as a white oil which did not crystallize. There was an appreciable pot residue. This product was clearly impure, having a minor, slower moving component not the starting phenol, as seen by TLC (on silica gel, with CH2Cl2 as a developing solvent). Fusion of a small amount of impure aldehyde with p-anisidine produced a crystalline anil which, on hydrolysis with dilute acid, produced an aldehyde sample free of this impurity. But as this sample also remained as an oil, the above crude product was used in the following preparation.

  To a solution of 3.8 g 3,4-dimethoxy-5-(n)-propoxybenzaldehyde in 50

  mL nitromethane, there was added 0.5 g anhydrous ammonium acetate.

  This was held at reflux for 50 min. The excess nitromethane was removed under vacuum and 2 volumes of boiling MeOH were added to the residue. The hot solution was decanted from some residual insolubles, and on cooling spontaneously crystallized. These solids were removed by filtration, washed sparingly with MeOH and air dried yielding 3.3 g yellow crystals of 3,4-dimethoxy-'-nitro-5-(n)-propoxynitrostyrene as yellow crystals melting at 79-81 !C. Recrystallization from MeOH or cyclohexane neither improved the mp nor freed the product from a residual opalescenceseen in the melt. Anal. (C13H17NO5) C,H.

  A solution of 1.5 g LAH in 30 mL anhydrous THF under He was cooled to 0 !C and vigorously stirred. There was added, dropwise, 1.0 mL of 100% H2SO4, followed by the dropwise addition of a solution of 2.3 g 3,4-dimethoxy-'-nitro-5-(n)-propoxynitrostyrene in 10 mL anhydrous THF, over the course of 5 min. The mixture was stirred at 0 !C for a while, and then brought to a reflux on the steam bath. After cooling again, the excess hydride was destroyed with IPA added dropwise, followed by the addition of about 10 mL of 10% NaOH which was sufficient to covert the solids to a white, granular form. These were removed by filtration, the filter cake washed with IPA, the mother liquor and filtrates were combined, and the solvents were removed under vacuum to yield an amber oil. This residue was added to 75 mL

  dilute H2SO4 which produced a gummy insoluble phase which was physically removed with a spatula. The aqueous phase was washed with 3x50 mL CH2Cl2. It was then made basic with 25% NaOH, and extracted with 2x75 mL CH2Cl2. The solvent was removed from these pooled extracts and the residue distilled at 106-116 !C at 0.2 mm/Hg to provide 1.3 g of the product as a colorless liquid. This was dissolved in 4 mL IPA, neutralized with about 20 drops of concentrated HCl, and diluted with 4 volumes of anhydrous Et2O added slowly with continuous stirring. A white crystalline salt crystallized out spontaneously and was isolated by filtration, washed first with IPA, then with Et2O, and air dried giving 1.3 g 3,4-dimethoxy-5-(n)-propoxyphenethylamine hydrochloride (MP) with a mp of 170-171 !C. Anal. (C13H22ClNO3) C,H.

  DOSAGE: greater than 240 mg.

  DURATION: unknown.

  QUALITATIVE COMMENTS: (with 160 mg) There might have been some disturbance at the three to four hour point, but it was extremely light if at all.

  (with 240 mg) No effects whatsoever.

  EXTENSIONS AND EXTRAPOLATIONS: The loss of activity on lengthening the carbon chain on the meta-oxygen from two to three (from metaescaline to metaproscaline) discouraged any further exploration at this specific point of the molecule. The isopropyl analog (3,4-dimethoxy-5-(i)-propoxyphenethylamine, metaisoproscaline, MIP) was started and carried along as far as the aldehyde, and abandoned with the discovery that metaproscaline was without activity. There were other fish to fry.

  138 MPM; 2,5-DIMETHOXY-4-(n)-PROPOXYAMPHETAMINE

  SYNTHESIS: To a solution of 68 g 2,5-dimethoxybenzaldehyde in 250 mL

  glacial acetic acid that had been warmed to 25 !C and well stirred, there was added, dropwise, 86 g of a 40% peracetic acid solution (in acetic acid). The reaction was exothermic, and the rate of addition was dictated by the need to maintain the internal temperature within a few degrees of 28 !C. External cooling was used as needed. The addition took 1 h, and when the reaction had clearly been completed (there was no further temperature rise) the entire reaction mixture was added to 3 volumes of H2O. The excess acid was neutralized with solid K2CO3. The dark solution was extracted with 3x100 mL Et2O, the extracts pooled, and stripped of solvent under vacuum to give 59 g of crude 2,4-dimethoxyphenyl formate. This was suspended in 200 mL 10%

  NaOH, and the mixture heated on the steam bath for 1 h. On cooling, the reaction mixture was washed with 2x200 mL methylene chloride, acidified with HCl, and extracted with 3x200 mL CH2Cl2. The extracts were pooled and the solvent removed under vacuum. There remained as residue, 47.4 g 2,5-dimethoxyphenol which was deep amber in color, but clear and fluid. It was homogenous by GC and completely correct by NMR. It was used without further purification.

  To a solution of 3.08 g 2,5-dimethoxyphenol in 20 g MeOH, there was added a solution of 1.26 g flaked KOH in 20 g hot MeOH. There was then added 2.46 g n-propyl bromide, and the mixture held at reflux for 2 h on the steam bath. This was quenched in 5 volumes H2O, made strongly basic with 10% NaOH, and extracted with 3x100 mL CH2Cl2.

  Removal of the solvent from the pooled extracts left 2.0 g of 1,4-dimethoxy-2-(n)-propoxybenzene as a clear, amber oil. The IR

  spectrum was appropriate, no phenol was present, and this residue was used in the following reaction without further purification or characterization.

  A mixture of 3.5 g N-methylformanilide and 4.0 g POCl3 was held at room temperature for 0.5 h producing a deep red color. To this there was added 2.0 g 1,4-dimethoxy-2-(n)-propoxybenzene, and the mixture was held on the steam bath for 1.75 h. It was then poured over 400 mL

  shaved ice, and vigorous stirring was maintained until the dark complex had completely broken up. This aqueous mixture was allowed to stand overnight, and the crude aldehyde solids that had formed were removed by filtration, water washed, and sucked as dry as possible.

  This 2.0 g damp material was crystallized from 20 mL boiling MeOH

  giving, after filtering and drying to constant weight, 1.4 g 2,5-dimethoxy-4-(n)-propoxybenzaldehyde as reddish-tan solids, with a mp of 97-98 !C. To the methanolic mother liquors of this crystallization there was added a gram of malononitrile and a few drops of triethylamine. The eventual addition of a little H2O

  encouraged the separation of crystals which were removed, and had a mp of 150-152 !C. Recrystallization from toluene gave gold-colored crystals of the benzalmalononitrile with a mp of 153.5-155 !C, but the melt remained slightly cloudy.

  To a solution of 1.4 g 2,5-dimethoxy-4-(n)-propoxybenzaldehyde and 0.65 g nitroethane in 4.4 g glacial acetic acid there was added 0.4 g anhydrous ammonium acetate, and the mixture was heated on the steam bath for 5 h. The addition of a modest amount of H2O and scratching with a glass rod produced crystal seed. The reaction was diluted with about 5 mL H2O, seeded, and allowed to stand at room temperature overnight. There was generated a crystalline product which was removed by filtration and air dried. There was thus obtained 0.6 g 1-(2,5-dimethoxy-4-(n)-propoxyphenyl)-2-nitropropene as yellow-orange crystals, with a mp of 83-84 !C. The addition of H2O to the mother liquors provided an additional 0.3 g of an orange solid which proved to be largely unreacted starting aldehyde.

  To a stirred, warm suspension of 0.5 g LAH in 20 mL anhydrous Et2O

  under a He atmosphere, there was added 0.6 g 1-(2,5-dimethoxy-4-(n)-propoxyphenyl)-2-nitropropene dissolved in a little anhydrous Et2O. The mixture was heated and stirred for a few h, and the excess hydride decomposed with 30 mL 1.5 N H2SO4. The two layers were separated, and 15 g potassium sodium tartrate was dissolved in the aqueous fraction. Aqueous NaOH was then added until the pH was >9, and this was then extracted with 3x50 mL CH2Cl2.

  Removal of the solvent under vacuum gave 0.7 g of an amber oil that was dissolved in anhydrous Et2O and saturated with anhydrous HCl gas.

  No crystals formed, and so the ether was remo
ved under vacuum, leaving a residue that set up to crystals that were then no longer soluble in ether. They were, however, very soluble in chloroform. These were ground under dry Et2O, removed by filtration, and air dried giving 0.35 g 2,5-dimethoxy-4-(n)-propoxyamphetamine hydrochloride (MPM) with a mp of 123 - 125 !C.

  DOSAGE: 30 mg or more.

  DURATION: probably short.

  QUALITATIVE COMMENTS: (with 15 mg) This is just barely threshold. A marginal intoxication at best. This level is producing less response that the 11 mg. trial of MEM, so the propoxy is off in potency. At four and a half hours I am out of whatever little there was.

  (with 30 mg) By the mid-second hour, I am at a valid plus one. I cannot identify the nature Q with eyes closed it would be lost, as it would also be if I were watching a play or movie. It would have been interesting to see where it could have gone. Seventh hour, completely clear.

  EXTENSIONS AND COMMENTARY: The 4-propoxy homologue of TMA-2 and MEM is clearly less active, and this has discouraged me from putting too much more effort in this direction. Three additional materials of this pattern were prepared and either shown to be even less active, or simply were not assayed at all. These are the 4-isopropoxy isomer (MIPM), the (n)-butoxy homologue (MBM), and the (n)-amyl homologue (MAM). They scarcely warrant separate recipes as they were all made in a manner similar to this one describing MPM.

  For the preparation of MIPM, the above phenol, 2,5-dimethoxyphenol was isopropylated with isopropyl bromide in methanolic KOH giving 2,5-dimethoxy-1-(i)-propoxybenzene as an oil. This formed the benzaldehyde with the standard Vilsmeier conditions, which melted at 77-78 !C from hexane and which gave a yellow malononitrile derivative melting at 171.5-173 !C. The nitrostyrene, from nitroethane in acetic acid was orange colored and melted at 100-101 !C from either methanol or hexane. This was reduced with lithium aluminum hydride in ether to give 2,5-dimethoxy-4-(i)-propoxyamphetamine hydrochloride (MIPM). The properties of the isolated salt were strange (soluble in acetone but not in water) and the microanalysis was low in the carbon value. The molecular structure had a pleasant appeal to it, with a complete reflection symmetry shown by the atoms of the amphetamine side chain and the isopropoxy side chain. But the nature of the actual product in hand had no appeal at all, and no assay was ever started.

  For the preparation of MBM, the starting phenol was alkylated to 2-(n)-butoxy-1,4-dimethoxybenzene in methanolic KOH with n-butyl bromide. The benzaldehyde melted at 79.5-81 !C from methanol, and formed a malononitrile derivative that had a melting point of 134.5-135 C. The nitrostyrene from the aldehyde and nitroethane in acetic acid crystallized from methanol with a mp of 71-72 !C. Lithium aluminum hydride reduction in ether gave the ether-insoluble chloroform-soluble product 4-(n)-butoxy-2,5-dimethoxyamphetamine hydrochloride (MBM) with a melting point of 128-130 !C. This product met all tests for structural integrity, and assays were started. At levels of up to 12.0 milligrams, there were no effects noted.

  As to the preparation of MAM, the exact same sequence was used, except for the employment of n-amyl bromide. The benzaldehyde crystallized from methanol with a mp of 79-80 !C, and formed a malononitrile derivative which was bright yellow and melted at 103-104 !C. The nitrostyrene, when pure, melted at 57-58.5 !C but proved very difficult to separate from the aldehyde. The final product, 4-(n)-amyl-2,5-dimethoxyamphetamine hydrochloride (MAM) was obtained by lithium aluminum hydride reduction in ether and melted at 125-127

  !C. It was assayed at up to 16 milligrams, at which level there was noted a heaviness in the chest and head at the 2-hour point, but no cardiovascular disturbance and no mydriasis. This was called an inactive level, and no higher one has yet been tried.

  139 ORTHO-DOT; 4,5-DIMETHOXY-2-METHYLTHIOAMPHETAMINE

  SYNTHESIS: To 26.4 g veratrol that was being magnetically stirred without any solvent, there was added 50 g chlorosulfonic acid a bit at a time over the course of 20 min. The reaction was exothermic, and evolved considerable HCl. The deeply colored mixture that resulted was poured over 400 mL crushed ice and when all had thawed, it was extracted with 2x150 mL CH2Cl2. Removal of the solvent under vacuum gave a residue that set up as a crystalline mass. The weight of the crude 3,4-dimethoxybenzenesulfonyl chloride was 37.1 g and it had a mp of 63-66 !C. Recrystallization raised this to 72-73 !C. Reaction with ammonium hydroxide gave the sulfonamide as colorless needles from EtOH, with a mp of 132-133 !C.

  The finely pulverized 3,4-dimethoxybenzenesulfonyl chloride (33 g) was added to 900 mL of crushed ice in a 2 L round-bottomed flask equipped with a heating mantle and reflux condenser. There was then added 55

  mL concentrated H2SO4 and, with vigorous mechanical stirring, there was added 50 g of zinc dust in small portions. This mixture was heated until a vigorous reaction ensued and refluxing was continued for 1.5 h. After cooling to room temperature and decantation from unreacted metallic zinc, the aqueous phase was extracted with 3x150 mL

  Et2O. The pooled extracts were washed once with saturated brine and the solvent was removed under vacuum. The residue was distilled to give 20.8 g of 3,4-dimethoxythiophenol boiling at 86-88 !C at 0.4

  mm/Hg.

  A solution of 10 g 3,4-dimethoxythiophenol in 50 mL absolute EtOH was protected from the air by an atmosphere of N2. There was added a solution of 5 g 85% KOH in 80 mL EtOH. This was followed by the addition of 6 mL methyl iodide, and the mixture was held at reflux for 30 min. This was poured into 200 mL H2O and extracted with 3x50 mL

  Et2O. The pooled extracts were washed once with aqueous sodium hydrosulfite, then the organic solvent was removed under vacuum. The residue was distilled to give 10.3 g of 3,4-dimethoxythioanisole with a bp of 94-95 !C at 0.4 mm/Hg. The product was a colorless oil that crystallized on standing. Its mp was 31-32 !C.

  To a mixture of 15 g POCl3 and 14 g N-methylformanilide that had been warmed briefly on the steam bath there was added 8.2 g of 3,4-dimethoxythioanisole, the exothermic reaction was heated on the steam bath for an additional 20 min, and then poured into 200 mL H2O.

  Stirring was continued until the insolubles had become completely loose and granular. These were removed by filtration, washed with H2O, sucked as dry as possible, and then recrystallized from 100 mL

  boiling EtOH. The product, 4,5-dimethoxy-2-(methylthio)benzaldehyde, was an off-white solid, weighing 8.05 g and having a mp of 112-113 !C.

  Anal. (C10H12O3S) C,H.

  A solution of 2.0 g 4,5-dimethoxy-2-(methylthio)benzaldehyde in 8 mL

  nitroethane was treated with 0.45 g anhydrous ammonium acetate and heated on the steam bath for 4.5 h. Removal of the excess solvent under vacuum gave a red residue which was dissolved in 5 mL boiling MeOH. There was the spontaneous formation of a crystalline product which was recrystallized from 25 mL boiling MeOH to give, after cooling, filtering and air drying, 1.85 g of 1-(4,5-dimethoxy-2-methylthiophenyl)-2-nitropropene as bright orange crystals with a mp of 104-105 !C. Anal. (C12H15NO4S) C,H,N.

  A suspension of 1.3 g LAH in 50 mL anhydrous THF was placed under an inert atmosphere and stirred magnetically. When this had been brought to reflux conditions, there was added, dropwise, 1.65 g of 1-(4,5-dimethoxy-2-methylthiophenyl)-2-nitropropene in 20 mL THF. The reaction mixture was maintained at reflux for 18 h. After being brought back to room temperature, the excess hydride was destroyed by the addition of 1.3 mL H2O in 10 mL THF. There was then added 1.3 mL

  of 3N NaOH followed by an additional 3.9 mL H2O. The loose, inorganic salts were removed by filtration, and the filter cake washed with additional 20 mL THF. The combined filtrate and washes were stripped of solvent under vacuum yielding a light yellow oil as a residue.

  This was dissolved in 20 mL IPA, neutralized with 0.9 mL concentrated HCl, and diluted with 200 mL anhydrous Et2O. There was thus formed 1.20 g of 4,5-dimethoxy-2-methylthioamphetamine hydrochloride (ORTHO-DOT) as a pale yellow crystalline product. This melted at 218-219.5 !C, and recrystallization from EtOH yielded a white product and increased the mp to 222-223 !C with decomposition Anal.

  (C12H20ClNO2S) C,
H,N.

  DOSAGE: greater than 25 mg.

  DURATION: unknown.

  QUALITATIVE COMMENTS: (with 25 mg) Vague awareness, with the feeling of an impending something. Light food sat uncomfortably. By the late afternoon there was absolutely nothing. Threshold at best.

  EXTENSIONS AND COMMENTARY: This material, ORTHO-DOT, can be looked at as the sulfur homologue of TMA-2 with the sulfur atom located in place of the oxygen at the 2-position of the molecule. At what level this compound might show activity is completely unknown, but wherever that might be, it is at a dosage greater than that for the PARA-DOT isomer, ALEPH-1 (or ALEPH), which was fully active at 10 milligrams (ALEPH can be looked at as TMA-2 with the sulfur atom located in place of the oxygen at the 4-position of the molecule). A lot of variations are easily makable based on this structure, but why bother? ALEPH is the much more appealing candidate for structural manipulation.

  140 P; PROSCALINE; 3,5-DIMETHOXY-4-(n)-PROPOXYPHENETHYLAMINE

  SYNTHESIS: A solution of 5.8 g of homosyringonitrile (see under E for its synthesis), 100 mg decyltriethylammonium iodide, and 10 g n-propyl bromide in 50 mL anhydrous acetone was treated with 6.9 g finely powdered anhydrous K2CO3 and held at reflux for 10 h. An additional 5

  g of n-propyl bromide was added to the mixture, and the refluxing continued for another 48 h. The mixture was filtered, the solids washed with acetone, and the combined filtrate and washes stripped of solvent under vacuum. The residue was suspended in acidified H2O, and extracted 3x175 mL CH2Cl2. The pooled extracts were washed with 2x50

  mL 5% NaOH, once with dilute HCl (which lightened the color of the extract) and then stripped of solvent under vacuum giving 9.0 g of a deep yellow oil. This was distilled at 132-142 !C at 0.3 mm/Hg to yield 4.8 g of 3,5-dimethoxy-4-(n)-propoxyphenylacetonitrile as a clear yellow oil. Anal. (C13H17NO3) C H N.