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All 19 posts Subject: 5-Hydroxyvanillin from 5-Iodovanillin Please login to post Down

Rhodium
(Chief Bee)
02-01-03 01:27
No 403132
User Picture       5-Hydroxyvanillin from 5-Iodovanillin
(Rated as: excellent)

The Synthesis Of 5-Hydroxyvanillin And 5-Hydroxyacetovanillone
Canadian Journal of Chemistry 40, 2175 (1962)

In connection with studies on the oxidation of lignin it became necessary to prepare various lignin model substances, one of which was 5-hydroxyvanillin (II).

An examination of the reported syntheses ^1,2,3,4 indicated that no simple method was available other than those requiring heated autoclaves.

A study was made, therefore, of the most promising procedure, which involved the copper-catalyzed hydrolysis of 5-halovanillin. It was early shown that 5-iodovanillin (III) underwent reaction much more readily than either the 5-bromo- or 5-chloro-derivatives. A satisfactory synthesis of II could indeed be obtained under reflux conditions, thus avoiding the need for reactions under pressure as had been recommended by previous workers. Of importance was the recognition that both the effectiveness of the catalyst as well as the nature of the products obtained were markedly dependent on the particular copper that was used. The authors maintained that only if a reproducible catalyst could be described would a synthetic procedure be of real value. This desire was achieved by the discovery that the addition of cupric ions provided the necessary catalytic activity for this alkaline hydrolysis reaction.

A study of the ratio of reactants, and the time and temperature of the reaction, resulted in a procedure whereby complete conversion of 5-iodovanillin (III) was achieved. The major product was 5-hydroxyvanillin (II) but in all cases a minor amount of the reductive dehalogenation product, vanillin (I), was also formed. The separation and identification of these products was made using both paper and gas-liquid chromatography. Separation and purification of the required II was readily achieved by recrystallization from benzene. The yield of purified product was 65-70% based on III.

This ready conversion of vanillin to 5-hydroxyvanillin prompted the attempt to similarly convert another lignin oxidation product, acetovanillone (IV, 3-Methoxy-4-Hydroxy-acetophenone), to the previously unreported 5-hydroxyacetovanillone (V). No difficulty was experienced in this synthesis. The only modification involved an increase in the time of reflux from 4.5 to 6.5 hours in order to convert all the 5-iodoacetovanillone (VI). As expected, the only other product to accompany the major product (V), but in much less amount, was the reductive dehalogenation compound, acetovanillone (IV). The structure of V was confirmed by analyses, absorption spectra, and conversion, by methylation, to the previously known 3,4,5-trimethoxyphenyl methyl ketone. The yield of recrystallized product was 45-50%.

A more complete discussion of the significance of the role of the copper catalyst and of the mechanism of formation of the products in such copper-catalyzed alkaline dehalogenation reactions is being prepared.

Experimental

Paper Chromatography

5-Hydroxyvanillin, vanillin, and 5-iodovanillin were separated by descending chromatography using Whatman No. 1 paper and the solvent system of n-butanol saturated with 2% ammonia. A saturated solution of 2,4-dinitrophenylhydrazine in 1 N hydrochloric acid was the spray reagent. For these compounds the Rf values were 0.38, 0.50, and 0.48 respectively.

Gas-Liquid Chromatography

A Beckman GC-2 chromatograph, with a thermal conductivity detector unit, was used after some modification to place the injection system as close as possible to one end of the column, and to make it more comparable electronically to the GC-2A. The column was made from 3 ft x 1/4 in. I.D. copper tubing and packed with Apiezon N grease on Fluoropak 80 (Wilkens Instrument and Research Inc.) in the ratio of 3 to 17. The chromatographic separations were effected at 220° using 30 p.s.i. helium carrier gas at a flow rate of 0.9 cc/second. Under these conditions the retention times for vanillin, 5-hydroxyvanillin, and 5-iodovanillin were 2.25, 4.7, and 12.0 minutes respectively, and for acetovanillone, 5-hydroxyacetovanillone, and 5-iodoacetovanillone they were 3.0, 6.7, and 19.5 minutes respectively.

5-Hydroxyvanillin

5-lodovanillin (2.8 g), hydrated cupric sulphate (1.6 g), and 4 N sodium hydroxide (76 ml) were refluxed (105°C) for 4.5 hours with continuous stirring under nitrogen. After cooling to 60-70°C, the mixture was filtered under suction and. the residue washed with hot water (3x10 ml). The alkaline solution was cooled to 10°C and acidified to pH 3-4, by the dropwise addition of concentrated hydrochloric acid. During this addition the mixture was stirred continuously and the temperature maintained below 25°C.

The resulting mixture, which contained a small amount of precipitate, was extracted continuously with ether for 16 hours. After being dried over anhydrous magnesium sulphate, the ether was removed (60-65°) to leave a dark gray product, 1.5 g. All but 0.10 g was dissolved in hot benzene, from which, after concentration to 75 ml, 5-hydroxyvanillin crystallized (1.15 g, 68%), m.p. 128-129°. Recrystallization from benzene, with charcoaling, gave a chromatographically pure product, mp 133-134°C; reported 132-134°C (2). With the exception of traces of 5-hydroxyvanillin the mother liquors contained only vanillin as indicated by gas-liquid chromatography.

5-Hydroxyacetovanillone

5-Iodoacetovanillone (2.9 g) (5), hydrated copper sulphate (1.6 g), and 4 N sodium hydroxide (76 ml) were refluxed (105°) for 6.5 hours with continuous stirring under nitrogen. As a result of a procedure similar to that used for the isolation of II, an ether extract (1.3 g) was obtained. Of this, 0.3 g was sparingly soluble in boiling benzene but the remainder crystallized on cooling of the benzene solution to yield crude 5-hydroxyacetovanillone (0.8 g, 44%), m.p. 162-166°C. A sample recrystallized from n-hexane-ethanol (5:1) melted at 166-167°C. Methylation with alkaline dimethylsulphate gave 3,4,5-trimethoxyphenyl methyl ketone, mp 77-78°C; mixed mp with an authentic sample, 77-78°C. The infrared spectrum was identical with that of the authentic sample.

References:
[1] Monatsh. 43, 93 (1922).
[2] J. Chem. Soc. 793 (1930).
[3] J. Am. Chem. Soc. 74, 4262 (1952).
[4] Can. J. Chem. 34, 1562 (1956).

Rhodium
(Chief Bee)
02-01-03 03:32
No 403175
User Picture       More related
(Rated as: excellent)

3,4,5-Trimethoxybenzaldehyde

5-Hydroxyvanillin was methylated with dimethyl sulfate and alkali following the procedure employed by Buck² for the methylation of vanillin to veratraldehyde, and the product was recrystallized from water to give 77% of pure 3,4,5-trimethoxybenzaldehyde melting at 74-75°C and not depressing a mixed melting point with authentic 3,4,5-trimethoxybenzaldehyde.

Syringaldehyde¹

A mixture of 10 g of recrystallized 3,4,5-trimethoxybenzaldehyde and 56 g of concentrated sulfuric acid was maintained at 40°C in a water-bath for 8 hours and then allowed to stand overnight at room temperature. The mixture was stirred into 100 ml of cold water and cooled. The clear solution was decanted from the little tar that separated and was extracted with ether. The ether was dried and distilled to yield 8.9 g (96%) of almost pure (as indicated by chromatography) syringaldehyde which, upon crystallization from petroleum ether (bp 65-110°C), melted at 109°C and did not depress the melting point of a mixture with authentic syringaldehyde. The use of crude 3,4,5-trimethoxybenzaldehyde or of longer reaction times resulted in poorer yields and in much cruder products.

Reaction of 5-Hydroxyvanillin with 1 Mole of KOH and 1 Mole of Dimethyl Sulfate¹

5-Hydroxyvanillin (16.8 g, 0.1 mole) was treated with 7.7 g (0.1 mole) of potassium hydroxide in 60 ml of water and with 12.6 g (0.1 mole) of dimethyl sulfate in the same manner employed for the complete methylation noted above. The cooled reaction mixture was extracted with ether and the ether was washed with 5% sodium hydroxide solution and then with water. The alkaline solution and washings were acidified and extracted with ether to yield 16.0 g of oily product. The original ether solution, when dried and distilled, yielded 3.3 g of crude 3,4,5-trimethoxybenzaldehyde melting at 70°C. Recrystallization from petroleum ether (bp 65-120°C) yielded crystals melting at 74-75°C which did not depress a mixed melting point with authentic 3,4,5-trimethoxybenzaldehyde.

The oily phenolic product was chromatographed from benzene on acid-washed Magnesol and developed with benzene-ethanol (100:1). The bands were located by streaking with 2,4-dinitrophenylhydrazine, potassium permanganate and ferric chloride. The leading band was eluted with acetone to yield 40% of 5-hydroxyveratraldehyde melting at 63-64°C and not depressing a mixed melting point with authentic 5-hydroxyveratraldehyde. The next band, upon elution, yielded 13% syringaldehyde melting at 109-110°C, and the upper band yielded 20% of unchanged 5-hydroxyvanillin melting at 132-133°C.

Reaction of 5-Bromovanillin with Sodium Hydroxide Solution in the Presence of Active Copper¹

Active copper powder was prepared according to Brewster and Groening³. A mixture of 155 g. of 5-bromovanillin, 50 g of freshly prepared active copper powder and 3000 ml of 8% sodium hydroxide solution was placed in a one-gallon stirring autoclave, heated to 200-210°C with stirring for one hour and allowed to cool with stirring. The copper was filtered, and the alkaline solution was acidified with dilute sulfuric acid. Some tar was removed by filtration, and the filtrate was concentrated to a small volume in a vacuum circulating evaporator below 50°C. The tar was boiled with water and filtered hot. Cooling of this filtrate yielded 4.4 g of crude 5-bromovanillic acid which, recrystallized from water in the presence of charcoal, yielded white needles melting at 226°C and not depressing a mixed melting point with authentic 5-bromovanillic acid.

The concentrated original aqueous filtrate deposited a crystalline precipitate on cooling. The crystals were filtered and recrystallized from water to yield 5.1 g of vanillic acid melting at 210-211°C. The filtrate was extracted with ether, and the ether was extracted successively with 21% sodium bisulfite, 8% sodium bicarbonate and 5% sodium hydroxide solutions. Work up of the bisulfite extract and chromatographing the residue yielded 6.6 g of vanillin and 1.8 g of 5-hydroxyvanillin. The bicarbonate solution yielded 0.8 g of vanillic acid. The sodium hydroxide extract, upon acidification and extraction with ether, yielded 13.6 g of phenolic oil which was distilled at 0.4 mmHg to give pure guaiacol, whose benzoate melted at 58-59°C and did not depress a mixed melting point with the benzoate prepared from authentic guaiacol. Guaiacol was also recovered from the condensate of the original vacuum concentration.

References:
[1] JACS 74, 4262 (1952)
[2] Organic Syntheses Coll Vol II, p 619
[3] Organic Syntheses Coll Vol II, p 446 Post 489647 (Rhodium: "Active copper powder from copper sulfate", Novel Discourse)

Rhodium
(Chief Bee)
08-20-03 00:12
No 454590
User Picture       Syringaldehyde From 5-Halovanillins
(Rated as: excellent)

The Reaction of 5-Bromovanillin and Sodium Methoxide
R. A. McIvor & J. M. Pepper
Can. J. Chem. 31, 298-302 (1953) (https://www.rhodium.ws/pdf/syringaldehyde-1.pdf)

The Synthesis of Syringaldehyde From Vanillin
J. M. Pepper & J. A. MacDonald
Can. J. Chem. 31, 476-483 (1953) (https://www.rhodium.ws/pdf/syringaldehyde-2.pdf)

Abstract

Syringaldehyde has been synthesized in high yields from vanillin. The process consists of the iodination of vanillin, followed by the interaction of the resultant 5-iodovanillin with sodium methoxide in anhydrous methanol at temperatures of 130 ±4°C. for one hour in the presence of a copper catalyst. Along with the syringaldehyde, small amounts of unchanged 5-iodovanillin and vanillin were always found in the reaction mixture. Analysis of the final product was made by an initial separation of the components by downward paper chromatography using a mixture of petroleum ether (bp 100-120°C), di-n-butyl ether, and water (10:1:1) as the developing agent for a period of 10 h. The separated compounds were extracted from the paper and their concentrations in alcoholic alkaline solutions determined spectrophotometrically. Under conditions by which 5-iodovanillin was converted to syringaldehyde in better than a 95% yield, 5-bromovanillin gave only a 61% yield and 5-chlorovanillin gave no detectable amounts of syringaldehyde.

Rhodium
(Chief Bee)
12-17-03 10:19
No 477375
User Picture       Vanillin --ICl--> 5-Iodovanillin

5-Iodovanillin
Nishinaga, A.; Matsuura, T.
J. Org. Chem. 29, 1812 (1964)

To a solution of 14.2 g. (0.1 mole) of vanillin in 400 ml. of dilute hydrochloric acid (18%) was added at 50°C 16.2 g. (0.1 mole) of iodine monochloride in 20 ml. of concentrated hydrochloric acid, and the mixture was allowed to stand for 48 h. The crystals which formed were collected by filtration. On standing, the filtrate deposited additional crystals and the total yield was 21.6g (81%). Recrystallization from dilute ethanol gave needles, mp 180-181°C (lit.^* mp 181-182°C).

^* G. Denis Thorn and C. B. Purves, The Oxidation of Pyrogallol and Vanillin by Alkaline Hypoiodite and Hypochlorite, Can. J. Chem. 32, 373-387 (1954) Post 489535 (Rhodium: "5-Chloro/5-Iodovanillin using Hypochlorite/iodite", Novel Discourse)
____ ___ __ _

3-Bromo-4-hydroxy-5-methoxybenzaldehyde (5-Bromovanillin)
A. Nazih, C. Benezra, J.-P. Lepoittevin
Chemical Research in Toxicology 6(2), 215-22 (1993)

To a strongly stirred ice-cooled solution of vanillin 7 (26 g; 0.17 mol) in CH₂Cl₂ (200 mL) was added dropwise bromine (8.76 mL; 0.171 mmol) in CH₂Cl₂ (10 mL). While bromine was added, an abundant precipitate was formed, and it was necessary to add more CH₂Cl₂ (50-100 mL) until the completion of bromine addition. After anight at room temperature, the reaction mixture was dissolved in THF (100 mL) and solvents were removed under reduced pressure. The crude mixture was taken up in CH₂Cl₂ (200 mL) and washed with a saturated solution of Na₂S₂O₃ (100 mL) until complete decolorization of bromine. After drying over MgSO₄, solvents were removed under vacuum and bromide 8 was purified by recrystallization from a mixture of hexane-ethyl acetate, yielding 31.6 g (80%) of a white solid: mp 164-165°C (lit.^* mp 164°C).

^* Mc Ivor, R. A., and Pepper, J. M. The reaction of 5-bromovanillin and sodium methoxide Can. J. Chem. 31, 298-302.
Post 454590 (Rhodium: "Syringaldehyde From 5-Halovanillins", Novel Discourse)

^{The Hive - Clandestine Chemists Without Borders}

Rhodium
(Chief Bee)
02-18-04 14:11
No 489535
User Picture       5-Chloro/5-Iodovanillin using Hypochlorite/iodite
(Rated as: excellent)

_{Studies in the Polyoxyphenol Series VI.}
The Oxidation of Pyrogallol and Vanillin by Alkaline Hypoiodite and Hypochlorite
G. Denis Thorn and C. B. Purves
Can. J. Chem. 32, 373-387 (1954) (https://www.rhodium.ws/pdf/halovanillin.hypohalite.pdf)

Abstract
Approximately 0.003 M solutions of pyrogallol and of vanillin in boric acid – sodium hydroxide buffers were used at 25°C to reduce hypoiodite and hypochlorite solutions made from sixfold molar amounts of the halogens. In all four cases the reduction reached a maximum in a narrow range near pH 9, and with hypoiodite the production of iodoform was restricted to this range. Slower secondary reductions were superimposed on very fast primary reactions. When oxidized with an equimolar amount of halogen near pH 8.5. Vanillin gave a 90% yield of 5-iodovanillin and 65% of the 5-chloro derivative. These yields decreased with increasing alkalinity as the halogenations became slower. A new, simple preparation of trichloropyrogallol in 72% yield consisted of carrying out the chlorination with 3 moles of hypochlorite at pH 12. An equilibrium between pyrogallol–hypoiodite and 3-hydroxy-1,2-benzoquinone-iodide appeared to exist at the same pH.

^{The Hive - Clandestine Chemists Without Borders}

sYnThOmAtIc
(Hive Addict)
02-18-04 23:45
No 489624
      Copper reference

Could somebody please post the information pertaining to the preparation of active copper referenced here...

Active copper powder was prepared according to Brewster and Groening [3]
[3] Organic Syntheses Coll Vol II, p 446

Rhodium
(Chief Bee)
02-19-04 00:55
No 489647
User Picture       Active copper powder from copper sulfate

Organic Syntheses is available online at http://www.orgsyn.org

An active copper powder can be prepared from copper sulfate. One hundred grams (0.4 mole) of copper sulfate (CuSO₄·5H₂O) is dissolved in 350 cc. of hot water in a 1-l. beaker. After cooling to room temperature 35 g. (0.53 gram atom) of zinc dust (more if necessary) is gradually added until the solution is decolorized. The precipitated copper is washed by decantation with water. Dilute hydrochloric acid (5%) is added to the precipitate to remove the excess of the zinc, and agitation is continued until the escape of hydrogen ceases. The copper powder is filtered, washed with water, and kept in a moist condition in a carefully stoppered bottle. Organic Syntheses, Coll. Vol. 2, pp. 445-446 (http://www.orgsyn.org/orgsyn/prep.asp?prep=cv2p0445)

^{The Hive - Clandestine Chemists Without Borders}

Nicodem
(Hive Bee)
02-19-04 09:12
No 489705
      Why not just 5-X-3,4-diMeO-PEA?

Every time I see one of these posts about geting to 5-OH-vaniline on the way to the mescaline I can't help wandering on the activities of 5-chloro-, 5-bromo- or 5-iodo-3,4-dimethoxy-phenylethylamine.
Can somebody tell my anything about their activity so I can sleep peacefully?

“The real drug-problem is that we need more and better drugs.” – J. Ott

Vitus_Verdegast
(Hive Addict)
02-19-04 15:03
No 489734
User Picture       Nicodem! :-)

That is exactly what I am wondering too for quite some time now. I was thinking of tasting 5-bromo-3,4-dimethoxyamphetamine and/or 5-bromo-3-methoxy-4-ethoxyamphetamine. As far as I know there is absolutely no information to be found on the activity of these two. At worst it could be a mood enhancer, if one can extrapolate from the unhalogenated analogs.

The only thing that troubles me is, will the aromatic halogen survive a NaBH₄, Zn/acid and/or Al(Hg) reduction? I know AlH₃ can be used, but obtaining LAH is impossible for me.

Franz Liszt - Mephisto Waltz (http://tinyurl.com/2kh8t)

Nicodem
(Hive Bee)
02-19-04 17:03
No 489747
      Should we call them metahaloescalines?

The only thing that troubles me is, will the aromatic halogen survive a NaBH4, Zn/acid and/or Al(Hg) reduction?

I keep on claiming that there is absolutely no way a arylhalogen would get dehalogenated with NaBH4, but I still didn't confirm that experimentaly (I will as soon as I'll find a way to formylate 2,5-diMeO-bromobenzene).
Anyway, teoreticaly NaBH4 can't do anything to those halogens, while the Zn/HCOOH reduction does not remove halogens from aromatic rings as the authors of that procedure confirmed with some examples.
Please report if you ever get to those "metahaloescalines".

“The real drug-problem is that we need more and better drugs.” – J. Ott

Vitus_Verdegast
(Hive Addict)
02-19-04 17:43
No 489751
User Picture       Yes but..

.. can you back this claim up with some references?

I can give some refs where dehalogenation occurs with NaBH₄. (Actually a friend of mine has them, I'll get them soon). Please prove me wrong! wink

An alternative could be to start with chlorovanillin, as an aromatic chlorine should be alot more thougher to remove than bromine.

EDIT: Metahaloescalines sounds very nice to me smile

EDIT2:
"Hopkins & Chisholm obtained a 90% yield of 5-chlorovanillin by permitting 1.5 moles of sodium hypochlorite to act on 1 mole of vanillin for one hour, apparantely in a sodium carbonate buffer."
Hopkins, C.Y. and Chisholm, M.J. Can. J. Research, B, 24, 208 (1946)

Does someone has access to this journal? I'll add this to the 'Wanted References' thread too.

Franz Liszt - Mephisto Waltz (http://tinyurl.com/2kh8t)

Nicodem
(Hive Bee)
02-19-04 20:53
No 489794
      OK, the Theory!
(Rated as: good read)

The theoretical evaluation of a possible dehalogenation in the preparation of metahaloescalines and 5-X-3-MeO-4-RO-amphetamines

First, there are (at least) two mechanism for hydride dehalogenation, one is a simple nucleophilic substitution S_N and the other a Single Electron Transfer (SET) radical mechanism. The later requires aprotic conditions and strong hydride reagents (like LiAlH4) so it’s out of question for NaBH4. The nucleophylic substitution R-X + BH₄^- => R-H + BH₃X^- is the formal equation for the former. This work quite good if the S_N2 mechanism for the substitution is possible (especially for activated R-X like benzylhalides, allylhalides, alpha-halogeno-ketones, -esters etc), but since here we have an arylhalide the only possible mechanism for that equation is an S_NAr. We know that this requires a very electron-poor aromatic ring or harsh (thermic) conditions and a copper catalyst.
Now, the question is: Does our 5-X-3,4-diMeO-nitrostyrene apply for the S_NAr?
First, let’s consider the effect of the two methoxies. They donate electron density to the benzene ring and therefore act protectively to the halogen smile . Secondly, drawing some resonance structures of the compound we see that the nitrovinyl group somewhat activate the positions 2, 4 and 6 for a S_NAr substitution frown but not the position 5 smile . Then thirdly, the temperature required for the NaBH4 reduction of the double bond is low and that’s good smile . And, the fourth thing is that the BH₄^- is not as good nucleophyle as the OH^- and even with this one and the S_NAr activating effect of –CHO you still need a catalyst and high temperature smile .
The sum is frown against smile smile smile smile . Not a bad result for so much theory crap. Now it’s time for a real-world experiment.

an aromatic chlorine should be alot more thougher to remove than bromine

The reactivity order for S_NAr is not the same as for S_N2. In this case is F >> Cl ~ Br > I, because the electronwithdrawing effects of the halogens are more important then their properties as a leaving group (a copper catalyst changes this because it induce a SET mechanism).

BTW:
Interestingly, the dehalogenation of the compounds (entries 6, 7 and 11) is not observed under these conditions. (NaBH4-wet clay coupled with microwave activation)
cited from Sodium Borohydride on Wet Clay (https://www.rhodium.ws/chemistry/mw.red-amination.txt)

and I also stumbled upon this doc that might be of general interest:
Merits of sodium borohydride reductions under phase transfer catalysis I (http://www.dishmangroup.com/merits-part-I.doc)
Merits of sodium borohydride reductions under phase transfer catalysis II (http://www.dishmangroup.com/merits-part-2.doc)

“The real drug-problem is that we need more and better drugs.” – J. Ott

Vitus_Verdegast
(Hive Addict)
02-20-04 18:26
No 490016
User Picture       Thanks for the explanation
(Rated as: excellent)

The article I was talking about is:

http://www.geocities.com/phorkys_hecate/cr0102967.pdf

Metal-Mediated Reductive Hydrodehalogenation of Organic Halides
Francisco Alonso, Irina P. Beletskaya and Miguel Yus
Chem. Rev. (2002) 102, 4009-4091
DOI:10.1021/cr0102967

The reactivity of group IIIA metals in hydrodehalogenation reactions is dominated by the use of the corresponding and diverse hydrides. For instance, borohydrides allow hydrodechlorination of alkyl and aryl halides, albeit high temperatures are required for polychlorinated aromatic compounds.

There is also a tidbit on Zn/HCOOH:
In situ generation of hydrogen from zinc and an organic acid such as acetic, formic, citric, or tartaric acid found application in the hydrodechlorination of polyhalogenated compounds such as DDT, DDD, DDE, and hexachlorobenzene, contained in contaminated soil, with 4-8 h contact times. Patent US5051030

However, they are most probably talking about ppm levels, so I guess this is irrelevant.

Now it’s time for a real-world experiment.

You have convinced me wink , I will start the project tonight.

http://www.movieconnection.it/schede/nosferatu.jpg

Rhodium
(Chief Bee)
03-05-04 03:11
No 493073
User Picture       Aromatic Chlorination by NaOCl(aq)
(Rated as: excellent)

Requested in Post 489751 (Vitus_Verdegast: "Yes but..", Novel Discourse) and retrieved by lugh:

Aromatic Chlorination by Aqueous Sodium Hypochlorite
C.Y. Hopkins and M. J. Chisholm
Can. J. Research B, 24, 208 (1946) (https://www.rhodium.ws/chemistry/5-chlorovanillin.hypochlorite.html)

Abstract
New instances of nuclear chlorination of benzene derivatives by the action of cold aqueous sodium hypochlorite are reported. The reaction gives good yields of monochloro derivatives when the orientation is favourable.

^{The Hive - Clandestine Chemists Without Borders}

Daphuk_up
(Hive Bee)
03-05-04 20:55
No 493219
      A perhaps noobish thought

SWID has always wondered about that too. In fact, from Vanillin, there seems to be 12 substituted compounds of possible intrest/activity.

The first six involve 4=methoxy, and 5= F, Cl, Br, I, Methoxy, Ethoxy. Obviously Trimethoxy is done.

The next six involve 4=ethoxy, and 5= F, Cl, Br, I, Methoxy, Ethoxy. The 4-ethoxy, 5-methoxy Escaline has been done, but why not two ethoxy groups?

Just a thought. tongue

Edited after SWID learned to count. crazy

Drug Chemists are Ta to a good Sm.

dennis_pro
(HyperLab Bee)
03-09-04 08:54
No 493893
User Picture       Shulgin done this work

Please read The Book (PHIKAL) again.
3,4-diethoxy-5-methoxy-PEA named "ASB" and so on...

With best regards,
Dennis Prochko aka Wolf

Daphuk_up
(Hive Bee)
03-09-04 22:04
No 494035
      Although..

Although the ASB was missed, it actually isn't one of the compounds in the above post. 3,4-diethoxy-5-methoxy-PEA has been explored, yes, but not 3-methoxy-4,5-diethoxy-PEA. It would be interesting to see what a rearrangment in this manner would do to the activity of the compound. (Just don't feed your cat a man-sized dose. frown )

Now, that being said, SWID does not want to give the impression he knows more than he does. He has yet to successfully synth any PEA, though as his learning and resources increase, the time of ascendence surely nears. shocked

So, if one of the above specific substances is in fact described in Phikal, please do SWID a favor and point it out for him. It would be greatly appreciated.

Drug Chemists are Ta to a good Sm.

moo
(Hive Bee)
03-09-04 22:37
No 494044
      3,4-diethoxy-5-methoxy-PEA has been explored,...

3,4-diethoxy-5-methoxy-PEA has been explored, yes, but not 3-methoxy-4,5-diethoxy-PEA

They are the same thing you know. Draw the molecules and see for yourself.

_{fear fear hate hate}

Daphuk_up
(Hive Bee)
03-10-04 22:55
No 494265
      Oh.

Oh, crap. blush

Ok, for some reason SWID was thinking of a two carbon difference on one side of the aliaphatic chain. (Without actually thinking about it.) SWIDs sincere thanks for pointing that out...he was chanting "bullshit" until he finished drawing the second one, and his jaw hit the table. tongue shocked blush

Drug Chemists are Ta to a good Sm.

	https://the-hive.archive.erowid.org	the-hive@erowid.org



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