(Official Hive Translator)
07-11-02 13:31
No 331379
(Rated as: excellent)
Here's a digest of some info i've found in Patent GB573120:
As you can see, there's quite something to think of. I purposefully posted this into Novel, not General Discourse, for i am very curious how one would go about synthing such a compound, and i want to ask you for ideas
In the patent they say they made the subst'd phenylacetone by
a) Chloromethylation of ortho-xylene
b) Cyanide coupling do give nitrile
c) Condensation of it w/acetoacetic ester in strong base (EtONa)
Now, the last two steps are quite tricky and require strictly unhyfrous conditions, but from step 1 it seems logical to assume that chloromethylation takes place in the 'correct' position. At least they say nothing about separation of positional isomers (but don't specify explicit procedures either, xcept for the last reductive amination step w/methanolic NH3/H2 under pressure).
That benzyl chloride can bee reacted w/hexamethylenetetramine in known manner to give the aldehyde - and then the traditional nitropropene stuff.
Anyway, thought someone might bee interested to know. What do you think?
Antoncho
(Distinctive Doe)
07-11-02 15:04
No 331409
Preparation of substituted benzaldehydes by reacting substituted benzene with carbon monoxide in the presence of metal halides and acids.
Patent US6080892
EXAMPLE 1
100.0 g of aluminum chloride (mol. wt. 133.34; 750 mmol) was poured over about 484.55 g of chlorotoluene in a 2 liter Paar.RTM.-brand stainless steel reaction vessel. Five drops of aqueous hydrochloric acid (concentrated) were then added and the vessel was sealed and purged two times with nitrogen at 60 psi. Then about 67.6 g of o-xylene (mol. wt. 106.17; 625 mmol) were charged to the vessel. The reactor was then purged three times with carbon monoxide at a pressure of about 110 psi. After the final purging, the vessel was vented and a final introduction of CO was made at a final pressure of about 110 psig, the pressure at which the reaction was maintained for the total reaction time of about 18 hours (the reaction temperature was maintained at about 5 DEG C. for the duration as well). After that time, the resultant mixture (exhibiting a dark orange color) was purged three times with nitrogen and poured into about 570 g of ice water (which turned the solution a dark purple), to which was then added 500 mL of cyclohexane (which turned the color to grey and produced a two-phase mixture). The top, organic layer was removed and washed three times with water using a separatory funnel and dried over magnesium sulfate. The residual organic phase was then distilled under a vacuum to remove o-xylene, cyclohexane, and chlorotoluene, and left about 74.36 g of the 3,4-dimethylbenzaldehyde target product (554 mmol; yield of approximately 88.7%).
EXAMPLE 2
99.4 g of aluminum chloride (mol. wt. 133.34; 745 mmol) and about 74.0 g of o-xylene (mol. wt. 106.17; 697 mmol) were charged to a 2 liter Paar.RTM.-brand stainless steel reaction vessel with about 150 mL of o-dichlorobenzene. The vessel was sealed, purged two times with nitrogen at 50 psi, then once with carbon monoxide at a pressure of 100 psi. After the final purging, the vessel was vented and a final introduction of CO was made at a final pressure of about 40 psig, the pressure at which the reaction was maintained for the total reaction time of about 14 hours (the reaction temperature was maintained at about 18-200 DEG C. for the duration as well). Once the reaction was complete, the resultant mixture was poured into about 600 g of ice water to produce about 900 mL of a two-phase mixture. The top, organic layer was removed and washed three times with water using a separatory funnel and dried over magnesium sulfate. The residual organic phase was then decolorized with activated charcoal and subsequently distilled under a vacuum to remove o-xylene (which has a boiling point of about 143-145 DEG C.), then o-dichlorobenzene (which has a boiling point of from about 174 to 180 DEG C.), and left about 50 g of the 3,4-dimethylbenzaldehyde target product (372.5 mmol; yield of approximately 50%).
Synthesis of aldehydes using the Gattermann-Koch reaction without activators.
Golubev, G. S.; Simonova, T. A.; Aleksandrov, V. N.; Gitis, S. S.
Zh. Prikl. Khim. (Leningrad) (1979), 52(4), 954-5.
ISSN: 0044-4618. Journal in Russian. CAN 91:56544
Abstract
Gattermann-Koch formylation of RC6H4Me (R = H, 2- and 3-Me) in C6H6 contg. AlCl3, HCO2H and SOCl2 or PCl5 gave 56.4-68.4% x,4-RMeC6H3CHO. (This article is on its way)
Methylbenzaldehydes
Patent JP54157534
Abstract
Methylbenzaldehydes were prepd. by liq.-phase autoxidn. of polymethylbenzenes having 2-4 Me groups in the presence of sol. Br compds. over >0.005 mol equiv sol. Co salts in 1.0 mol equiv. satd. fatty acids or their anhydrides as solvents at <85° to a point of <95% conversion. Thus, a liq. mixt. of 1:12.5:0.3:0.03 M 1,3,5-Me3C6H3, HOAc, Co(OAc)2.4H2O, and Br was heated 30 min at 49-51° with introduction of O to give dimethylbenzaldehydes with 61% selectivity and 59% conversion, vs. 23 and 58%, resp., without Br. Similarly oxidized were 1,2,4,5-Me4C6H2, o-, m-, and p-xylene, and 1,2,4-Me3C6H3.
Process for the preparation of substituted benzaldehydes
Patent US4622429
This is the traditional gattermann-koch reaction which requires high pressure(~1000psi) HCL and CO.
Those who give up essential liberties for temporary safety deserve neither liberty nor safety
(Hive Bee)
07-11-02 15:47
No 331423
If you've got, ortho-xylene, then simply formylate it by whichever method is most accessible to you to get 3,4-dimethylbenzaldehyde. After that, the hardest part is obtaining the nitroethane and deciding how you would like to reduce the beta-nitropropene.
(Chief Bee)
07-14-02 14:34
No 332494
This seems to be a pretty interesting substance, it is halfway between amphetamine and IAP, the indanyl-aminopropane with distinct serotonergic effects. I'd say that the same synthetic route would apply to o-Xylene as for Indane.
(Stranger)
07-14-02 16:33
No 332550
Get some 1,2,3-trimethylbenzene, formylate it, condense that with MeNO2, reduce and let us know how things turn out!
(Hive Bee)
07-15-02 00:12
No 332734
shulgin mentioned 3,4,5-trimethylamphetamine as a very powerful compound. I've looked for 1,2,3-trimethylbenzene and found nothing commercially available. It was mentioned in a belgian chem. supplier catalogue, but upon request they were unable to supply this substance
.
(Stranger)
07-15-02 14:47
No 332964
Buy some ortho-xylene. React your ortho-xylene with stannous chloride and CH2Cl2-O-CH3 to yield 3,4-dimethylbenzaldehyde. Take your 3,4-dimethylbenzaldehyde and react with AlCl3 and MeX, where X is Cl, Br or I. Runaway alkylation of the benzene ring shouldn't be a problem because the aldehyde is electron withdrawing and thus
deactivating to the aromatic nucleus. Also, the carboxaldehyde group is also meta-directing (towards the 5-position), so the 5-position will be the first to be added on to in this example. If runaway alkylation does turn out to be a problem experimentally, use a less powerful Lewis acid such as FeCl3 or ZnCl2 even. Finally, if all else fails do a Friedel Crafts acylation followed by a Zn/Hg reduction of the carbonyl group to get your 3,4,5-trimethylbenzaldehyde. In the case of the FC acylation, as opposed to the shorter FC alkylation, the electron withdrawing carbonyl group deactivates the ring even further and there will be absolutely no further alkylation of the benzene ring after that.
Viola...3,4,5-trimethlylbenzaldehyde.
However, keep in mind I was really only half seriously mentioning actually making this compound, especially the amphetamine derivative of it. Methyl groups are mean, while ethyl is ethereal. I would think following this outline would lead to a very bad trip, but what is candy if not poison?
(Stunning)
07-28-02 09:36
No 338083
It's really interesting stuff.
To my sincerely regret my knowledges in farma are trifling...
But, what are you think about activity of amphetamine (TMA-6 analog!), which produced from mesitilene (2,4,6-trimethylbenzaldehyde)???
The description of mesitilene synthesis you may find at http://www.orgsyn.org/orgsyn/prep.asp?pr
There's a hole in our soul that we fill with dope
And we're feeling fine.
(Chief Bee)
07-29-02 21:05
No 338791
Hey, definitely check Post 301119 (terbium: "2,5-dimethylamphetamine", Newbee Forum), and Post 338530 (Dr_Heckyll: "YAA - Yet Another Amphetamine", Stimulants) is also of interest.
(Hive Bee)
07-29-02 21:48
No 338807
Nemo_Tenetur: I've looked for 1,2,3-trimethylbenzene and found nothing commercially available. It was mentioned in a belgian chem. supplier catalogue, but upon request they were unable to supply this substance.
Looks like you didn't do your homework thoroughly. 1,2,3-TRIMETHYLBENZENE (CAS# 526-73-8) is available and cheap:
-> TCI 500 ml ~ $90
-> Lancaster 1L ~ $90
-> ICN 100g ~ $700 (they always have insane prices, I wonder who buys from them? The gov't probably...)
-> ACROS 100 ml ~ $20
Didn't enquire, though, but it appears to be a common compound...
And what about 1,2,4-trimethylbenzene, which is even cheaper?
-> ACROS 2.5 LT ~ $50
-> and many others
Hell, where are methylbenzenes reactive? Ortho, meta or para? Do they react like phenols and phenol ethers? Any hardcore refs? Or do I have to move my lazy ass to the library and find out?
Have a list long as a roll of toilette paper to research in the library already .For every molecule there is a moron thinking it will be a great drug
(Chief Bee)
07-29-02 22:38
No 338835
Methylbenzenes are ortho, para-directing, but much less reactive than phenols and phenol ethers - therefore only certain formylation methods can be used on them to produce benzaldehydes.
Formylation of 1,2,3-trimethylbenzene should give ~60-70% 2,3,4-trimethylbenzaldehyde and ~30-40% 3,4,5-trimethylbenzaldehyde.
(Stranger)
07-30-02 16:12
No 339124
That looks like a 'stunning' idea in deed to me, Tricky, but ethyl would be preferable. Maybe even throw in a methoxy or to to keep it trippy/gentle, for example psi-DOET (4-ethyl-2,6-dimethoxy-AMP).
BTW, I love your music!
.
While in the land of the limbo, beware the green eyed monsters.--Tiresias3
"Follow where Mary goes,
Cherish the things she knows.
Says if I change my stride,
Then I'll fly.
She makes me me wanna cry,
and change my stride.
Then I'll fly."--Tricky, _Pre-Millenium Tension_
(Hive Addict)
07-30-02 16:39
No 339127
Ethyls are nasty. See 2C-E.
(Distinctive Doe)
08-03-02 22:38
No 340943
2C-E sounds VERY interesting.
Those who give up essential liberties for temporary safety deserve neither liberty nor safety
(Hive Bee)
08-04-02 04:31
No 341056
2C-E is very interesting. It seems to have been used as a therapeutic aid in Europe.
(Pioneer Researcher)
08-04-02 06:18
No 341095
I know (absolutely sure) that 2C-D has been used in Europe as therapetical aid. I talked a while with a friend that was there and told me it is interesting, it's still not illegal, but I don't see a easy way to make more than anecdothical amounts.
(Hive Bee)
08-04-02 07:16
No 341109
If 2C-E is to be made from scratch it seems a bit messy as all the 2,5-dimethoxy-4-alkyl-PEA´s. But I happen to have the fortune to be able to buy whatever benzaldehydes I need in kilo amounts.
(Hive Addict)
08-05-02 12:28
No 341763
After I took one dosage of 2C-E (12 mg), I suffered from mental flashbacks for at least half a year. And that includes severe anxiety for a number of seconds. To the point where you'd want to give up anything in order for the torture to stop. A mental institution almost sounds like *fun* when you're having those attacks.
Anyway, I don't know whether it's me, my neurochemistry, the results of a `typical phenethylamine head trip' (I guess high dosage 2CT2/2CT7 can be just as nasty), or the compound itself. However, I tend to agree with Shulgin: `for the moment, let it rest as being a difficult and worth-while material'. Once a year, at most.
(Moderator)
04-07-03 11:12
No 424559
To bring this up again (and back to the topic): 3,4-dimethyl-benzoic acid can be bought from Aldrich 10 g / €34.30, 100 g €168.30). Reduction + Oxidation would be an easy and safe way to 3,4-dimethyl-benzaldehyde. Who knows, maybe it's more MDMA-like than being a stimulant...
(Moderator)
04-08-03 04:10
No 424735
If you want to save some money you can go this way:
4-methyl-benzaldehyde (500 g / €59.60) __> 3-bromo-4-methyl-benzaldehyde __> 3-bromo-4-methyl-benzaldehyde acetal __> 3,4-dimethyl-benzaldehyde
using an aromatic bromination / Grignard substitution sequence.
(Chief Bee)
04-08-03 04:46
No 424737
4-methyl-benzaldehyde -> 3-bromo-4-methyl-benzaldehyde
Org Prep Proced Int 6, 251 (1974)
3-bromo-4-methyl-benzaldehyde -> 3-bromo-4-methyl-benzaldehyde ethylene acetal (I can post this if there is any interest)
J Med Chem 33(3), 976 (1990)
(Stranger)
04-08-03 10:33
No 424784
hi bees,
found an interesting tid bit in sasha's book regarding
the 4-methyl and 3,4-dimethyl-amphetamine.
from pihkal #54:
"The 3,4-isomer, 3,4-dimethylamphetamine or xylopropamine, is an adrenergic agent and it has been found to be an analgesic in man at as little as 10 milligrams. This was assayed, rather remarkably, by attaching electrodes to the tooth fillings of the experimental subjects. But with this base, cardiovascular effects were not observed until doses of about 100 milligrams were administered, and toxic effects (nausea and vomiting) were reported at 150 milligrams. There was no suggestion of anything psychedelic.
All three isomers of monomethylamphetamine have also been looked at in man. The ortho- and meta-isomers, 2-methyl- (and 3-methyl- ) amphetamine are weak anorexics. At doses of up to 150 milligrams orally, there were signs of stimulation noted--talkativeness and loss of appetite. The para-isomer, 4-methyl-amphetamine or Aptrol, is more potent. At 75 milligrams (orally, in man) there is clear adrenergic stimulation, and at twice this dosage there are signs of mild toxicity such as salivation, coughing and vomiting."
I believe the ref sasha is referring to is:
Harris, S. C. and Worly, R. C. (1957). Analgesic
properties of xylopropamine, Proc. Soc. Exp.
Biol. Med. 95:212-215.
Some further info from Glennon on the subject:
Higgs RA, Glennon RA.
Pharmacol Biochem Behav 1990 Dec;37(4):835-7
Stimulus properties of ring-methyl amphetamine analogs.
"There are three possible ring-substituted methyl amphetamines (or tolylaminopropanes; TAPs): oTAP, mTAP and pTAP. These agents are positional isomers of methamphetamine. Although all three isomers have been previously reported to possess amphetamine-like character, few studies have examined all three agents in comparison with (+)amphetamine. Using rats trained to discriminate 1 mg/kg of (+)amphetamine from saline under a variable-interval 15-sec schedule of reinforcement, tests of stimulus generalization were conducted with the three positional isomers. Only oTAP (ED50 dose = 4.1 mg/kg) completely substituted for (+)amphetamine. mTAP and pTAP resulted only in partial (ca. 50% amphetamine-appropriate responding) generalization. It is concluded that oTAP is capable of producing amphetamine-like stimulus effects and that it is approximately one-tenth as potent as (+)amphetamine; however, because the partial generalization produced by mTAP and pTAP was followed by disruption of behavior at slightly higher doses, it cannot be reliably stated that these latter two isomers lack amphetamine-like character."
It could be guestimated that perhaps the p and m position
methyl's may be effecting serotonin in similar fashion as other p sub amphetamines. specially considering the recent
report of 4-methyl-methcat having a rush akin to honey.
seems like some toxicity testing would be prudent measure
before engaging in extensive trials, especially considering p-halogen, p-methoxy, and p-methylthio toxicity.
happy hunting!
toadie
(Moderator)
04-08-03 12:13
No 424815
This is the Glennon article: DOI:10.1016/0091-3057(90)90571-X (using the new [do
(Hive Bee)
04-08-03 13:38
No 424832
It could be guestimated that perhaps the p and m position
methyl's may be effecting serotonin in similar fashion as other p sub amphetamines. specially considering the recent
report of 4-methyl-methcat having a rush akin to honey.
Well I certainly agree there
. The high is rather short lasting, only about 45 minutes if snorted. Maybe this could be extended to a few hours if it was eaten. The rush of 4-methyl methcat seems to be more than just plain stimulant, so maybe there is something in the serotonin-related 4-position theory here too.Note also that this bee's toxicity tests took him to 600mg intransally over a period of about 6 hours, with no noticeable side effects, except for the obvious lack of appetite and difficulty concentrating. A lower dosage would have been more sensible, but at least we now know that 4-methylmethcathinone is 'safe' at 600mg whereas 150mg 4-methylamphetamine produces mild toxic symptoms. It would probably be wise to proceed with care on any trial of 3,4-dimethylamphetamine; it's structural similarity to indanylamphetamine which Rhodium says to proceed with caution on in ../rhodium /iap.htm
(Distinctive Doe)
04-08-03 23:05
No 424991
although it would be nice for any bee who actually knows something about pharmacology to give a more knowledgeable reply.
If only brains were that simple. We wouldn't even need to do research. There is no way to look at a molecule and say how it will act. Sure you can make an educated guess, but how many people here look at and think of these things in 3D which is reality. Thats the first little step towards an educated guess on activity, then there are probly 5 other important factors to add in.
We don't have anyone here who knows anything about pharmacology do we?
Might we have a handful of the most knowledgeable on the planet?
Maybee...
To bad foxy's not one
04-09-03 18:41
(Rated as: insignificant)
(Hive Bee)
04-09-03 19:12
No 425299
(Rated as: Couch topic)
You are throwing wild guesses of the actions of compounds yet unexplored in the air... just like a user called Redmonn_16 did a few months ago. It is interesting to see you quote the Wu Tang Clan too, just like he did in a PM. The sketchy outlines of synthetical routes also sound quite familiar not to mention the attitude. I wonder, would he had needed to register a new account?
Would you like someone to test these compounds for you, sir?
"Don't talk the talk if you can't walk the walk" --the Wu Tang Clan
(Official Hive Translator)
04-09-03 19:51
No 425305
(Rated as: Couch topic)
moo:
(Hive Bee)
04-10-03 12:27
No 425451
Okay, firstly way to go moo!! Yeah!
Secondly, about possible syntheses 4-methyl compounds, could something like this work for say DOM?...
2,5-Dimethoxybenzaldehyde ---> Clemmensen ---> 2,5-Dimethoxytoluene?
SWIM has a reference where they do the exact same reduction on vanillin to obtain 1-methyl-3-methoxy-4-hydroxybenzene in 60-65% yield. Is this reduction of aldehydes applicable to other structures?
Thirdly, about making the -propyl compounds. Would a Clemmensen reduce an allyl group??? Could one go like this for 2C-P?...
2,5-Dimethoxyallylbenzene ---> Clemmensen ---> 2,5-Dimethoxypropylbenzene??
2,5-Dimethoxyallylbenzene is outlined on Rhodium's, seems facile. That would be GREAT!!
Finally, SWIM still can't figure out a way to make the 4-ethyl compounds. 2C-E looks like such an amazing compound, contrary to what yellium noted. It seems one has to make the acetophenone with non-OTC chems. Then reduce with Clemmensen, then formylate with most possibly a chloromethylation.
(Stranger)
04-12-03 14:20
No 426145
2,5-Dimethoxybenzaldehyde will most definetly reduced by clemmensen to the toluen. It seems like waste of benzaldehyde! About a allyl group being reduced, it might work to make the propyl. It seems like a good way to make 4-propyl compounds, good idea! Of course stronger reducing agents will work, but clemmensen? not sure. The moderator Rhodium know best here.
For your trouble in 2C-E, how about this idea. You can make acetic anhydride OTC, so reflux with 1,4-dimethoxybenzene to obtain the acetate (don't have patent# with now, but they say any CH3COA work. Email, you remember the address right?). React acetate with 1.2 mol equiv. AlCl3 (not so OTC, but a chemist named mountain_girl mentions making AlBr3 easy). This gives the acetophenone. No acetyl chloride.
Also, GB patent #633,724 shows use of P2O5(again not OTC) and acetic acid to make acetophenone.
(Moderator)
04-14-03 14:21
No 426695
I just found this patent as an old printout between my documents: Patent GB1036290. It contains a procedure to 3,4-methyl-amphetamine (Xylopropamine) from 1-amino-3,4-dimethyl-benzene.
(Hive Addict)
04-14-03 22:10
No 426854
(Rated as: excellent)
GB Patent 1036290
A Process for the Manfacture of Phenyl-Amino-Propane Derivatives
Abstract:
The process provided by the present invention, which is a technically simple process and enables the xylopropamine to be obtained in a pure form (that is to say, free from undesired isomers), comprises diazotizing 1-amino-3,4-dimethylbenzene, reacting the diazonium product with formaldoxime, hydrolyzing the resulting 3,4-dimethylbenzaldoxime, condensing the 3,4-dimethylbenzaldehyde obtained with nitroethane, reducing the resulting 3,4-beta-trimethyl-beta-nitrostyrene and, if desired, converting the resulting 1-(3,4-dimethylphenyl)-2-aminopropane into an acid addition salt.
Example 1:
A mixture of 46g of paraformaldehyde, 105g of hydroxylamine hydrochloride and 680ml of water heated on the steam-bath in a 2L RB flask until complete solution had occurred. 204g of sodium acetate were then added and the solution obtained was boiled under reflux on an oil-bath for 15-20minutes. The solution was then cooled to 10*C and decanted into a 6L flask which was fitted with a stirring device, a reflux condensor, a thermometer and a dropping funnel. 4g of sodium sulfate, 25g of copper sulfate and a solution of 660g of sodium acetate in 720ml of water were then added to the solution.
121g of 1-amino-3,4-dimethyl-benzene in powder form were introduced into a mixture of 228ml of concentrated hydrochloric acid, 200ml of water and 400g of ice; 1-amino-3,4-dimethylbenzene hydrochloride crystallized out. A solution of 70g of sodium nitrite in 100ml of water was added dropwise with stirring and ice-cooling in such manner that the temperature did not rise above 5*C. A solution of 130g of sodium acetate in 200ml of water was then added and the ice-cooled diazonium solution thus obtained was added dropwise over 30 minutes to the solution of formaldoxime obtained according to the data in the first paragraph of this Example; during the addition, the temperature was held at 10-15*C. A black tar-like precitate formed. The mixture was stirred for ca 1 hour and then acidified with 200-300 ml of concentrated hydrochloric acid. A furthur 920ml of concentrated hydrochloric acid were added and the mixture was heated at reflux for 2 hours and then distilled with steam. The distillate (ca 5L) was neutralized with 350g of sodium bicarbonate and extracted with 1L of ether. The yellow oily residue obtained after concentration of the ether extract was heated at ca 60*C with stirring for 2 hours with 360ml of a 40% solution of sodium sulfite. About 1300ml of water and 500ml of ether were added to the cooled mixture and the ethereal phase was separated. The aqueous solution was heated at reflux for 30 minutes with 180ml of conc. sulfuric acid and 180 ml of water. The mixture was then extracted with about 1000ml of ether and the extract was dried over sodium sulfate and evaporated to dryness. The yellowish residue was distilled at 97-99*C/10mmHg to yield 59g of pure 3,4-dimethylbenzaldehyde as a colorless liquid that had; nD 23 = 1.5490
A mixture of 100g of 3,4-dimethylbenzaldehyde, 100ml of toluene, 180g of nitroethane, 5 ml of butyl amine, 5ml of glacial acetic acid and 0.35g of paratoluenesulfonic acid was heated at reflux in a 500ml rb flask fitted with a reflux condensor and a water separator. The resulting solution was concentrated under reduced pressure and the oily residue taken up in 100ml of absolute ethanol. Upon cooling to –10*C, yellow crystals were filtered off and washed with ice-cold ethanol and air-dried. 118g of material were obtained.
The alcoholic mother liquor was evaporated to dryness and the residue was taken up in ether. The resulting solution was washed with aqueous sodium carbonate, water, 3N HCl and once again with water and dried over sodium sulfate. The solvent was evaporated and the residue (ca 20g) was distilled under reduced pressure. The fraction boiling at 155-160*C/9mmHg was collected, dissolved in 12ml of absolute ethanol and crystallized at –10*C to yield ca 9g of material. Two crops of material were combined to give 127g of yellow crystals that had; MP: 36-37*C Which after recrystallization from 130ml of methanol gave 121g of pure 3,4-beta-trimethyl-beta-nitrostyrene in the form of light yellow crystals that had; MP: 37-38*C
19.1g of the product above in a mix of 200ml of methanol and 2ml of 48% HBr were hydrogenated at RT in a 500ml hydrogenation flask in the presence of 5g of 5% Pd/C. 0.2mol of H2 was taken up within ca 8 hours, after which time the catalyst was filtered and 5ml of 20% methanolic solution of ammonia were added to the solution. The solution was evaporated to dryness and the residue was taken up in 200ml of ether. Undissolved ammonium hydrobromide was filtered and the rest was hydrogenated in the presence of 15g of raney nickel which had previously been washed with methanol. About 0.2 mol of H2 was taken up in 8 hours. The catalyst was then filtered and the solution was concentrated. The residue was distilled under reduced pressure, the fraction which went over at 110-112*C/10mmHg being separated. 14g of pure 1-(3,4-dimethylphenyl)-2-amino-propane were obtained in the form of a clear liquid that had; nD 23 = 1.5178
The reduction can also be done using LiAlH4
1-(3,4-dimethylphenyl)-2-aminopropane can also be obtained from the nitrostyrene in the following manner:
13.4g LiAlH4 and 360ml of absolute ether were filled into a 1.5L, three-necked flask fitted with a reflux condensor and dropping funnel. A solution of 19.1g of 3,4-beta-trimethyl-beta-nitrostyrene in 240ml of absolute ether was added dropwise with stirring within 2 hours and the mix obtained was boiled under reflux for 2 hours. The mix was then cooled by means of an ice-bath and 90 ml of ice-cooled water were slowly added dropwise. A white granular precipitate formed and was filtered off by suction and thoroughly washed with ether. The ethereal solution obtained was dried over sodium sulfate and concentrated. The residue was distilled at 110-112*C/10mmHg to give 12.2g of pure 1-(3,4-dimethylphenyl)-2-aminopropane.
Also:
The fumarate salt was colorless crystals that had; MP: 187-188*C
The hydrochloride was colorless crystals that had; MP: 169-170*C