Diafrag (ChemLover) 05-25-02 01:52 No 313951 |
russian article about 3substituted phenethylamines (Rated as: excellent) |
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Someone of you beez asked of this ref. Synthesis of 3-substituted phenylethylamines by catalitic reduction of nitrostyrenes. Synthesis of starting aldehydes [8, 9, 10] was carried out by known methods, namely introduction in a molecule of vanillin I- or Br-atom, with the subsequent replacement of halogen on - oxy- or alkoxy groups. The appropriate styrenes [11, 12] were obtained by condensation of aldehydes with nitromethane with the catalytic additives of methylamine. The carrying out of condensation at the presence of ammonium acetate in acetic acid instead of methylamine greatly reduced yield or yielded slowly decomposed products. 3-methoxy-4,5-dioxyphenylethylamine A suspension of 3 g 3-methoxy-4,5-dioxynitrostyren in 80 mls of acetic acid with simultaneous feeding of Hydrogenium is added to 3 g of vigorously shaken palladium black in 65 mls of glacial acetic acid and 2 mls of concentrated sulfuric acid previously sated with Hydrogenium for 30 minutes. After end of absorbtion of calculated amount of Hydrogenium the catalyst was separated, acetic acid was distilled off in vacuum; the stayed oil was cooled to the beginning of crystallization. The deposit was filtered off and washed on the filter with 15 mls of acetone. Yield 2 g (51,5 %), m. p. 107-108 deg. C.(from water). then they make freebase and hydrocloride. freebase m. p. 173-174 deg. C.(from alcohol) hydrocloride m. p. 198-199 deg. C.(from alcohol) Similarly 3,5-dimethoxy-4-oxyfhenylethylamine and 3-methoxy-4-oxy-5-bromfhenylethylamine were obtained. 3,5-dimethoxy-4-oxyfhenylethylamine freebase m. p. 153-154 deg. C.(from alcohol) bisulpfate m. p. 143-144 deg. C(from dry alcohol) hydrocloride m. p. 256-257 deg. C.(from alcohol and ether 1:2) Yield 54.4 of bisulpfate 3-methoxy-4-oxy-5-bromfhenylethylamine freebase m. p. 169-170 deg. C.(from m-xylene) bisulpfate m. p. 217-218 deg. C(from alcohol) hydrocloride m. p. 176-177 deg. C.(from alcohol and ether 1:2) Yield 49.8 of bisulpfate Refs: I ask those who have access to this articles to post them here. [11] Ð. Smith. J. Chem. Soc., 1958, 3740 [12] J. Pepper, J.MacDonald. Canad. J. Chem. 31, 476(1953) [8] F. Benington, R. Morin, L. Clarc, J. Org. Chem., 20, 1292(1955) [9] F. Benington, R. Morin, L. Clarc, J. Am. Chem. Soc.,76. 5555(1954) [10] is a Russian journal and I'll try to find it soon. |
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Rhodium (Chief Bee) 05-25-02 02:42 No 313962 |
Some questions | Bookmark | ||||||
Hi Diafrag, Very nice post! From which journal did you copy this information? I took the liberty to correct the spelling and grammar of your post below for easier reading by western bees, I hope you don't mind. Questions: * Which of the references #8-12 do you want us to retrieve for you? All of them except #10? * In the synthesis of 3-methoxy-4,5-dihydroxy-phenylethylamine * Does the reference say how the bisulfate salts were prepared? Neutralization of an alcoholic solution of the freebase with alcoholic sulfuric acid? * It is somewhat unclear how the hydrogenation is performed. Is this correct: Pd Black, acetic acid and H2SO4 is bubbled with H2 for 30 min, then the nitrostyrene in acetic acid is added, and everything is then shaked vigorously while introducing H2 at 1 atm pressure until the theoretical amout of H2 is absorbed? Is it conducted at room temp?
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Diafrag (ChemLover) 05-25-02 14:37 No 314140 |
Hi Rhodium! glad to see you interested. | Bookmark | ||||||
Hi Rhodium! glad to see you interested. and thanx for your corrections, now it looks much better. i don't have any experience in such translations and your remarks will help me. so, answers: it is from (I don't know the correct translation, hope you understand) Journal of General Chemistry, 32(1962); p.2661 The authors are K. M. Dumaev and I. S. Belostotskaya. the original in russian is here www.chemlover.narod.ru/articles/article1 then, 1. You cought me right, but I think not only me is eager to see how this lovely things can be obtained, maybe there will be some interesting and unknown information or some references. in my library there is no foreign journals at all. 2,3. I think the filtered precipitate was bisulfate, not acetate. IMHO sulfuric acid is hygroscopic and when distilling it will fly latter, so the salt must be bisulfate. they don't say anything about obtaining bisulfate, after saying they've got this precipitate and washed it with acetone the article goes on: To 0,9 g of amine bisulfate was added 6 mls of water and 0,9 mls of concentrated solution of ammonia. Precipitated 3-methoxy-4,5-dioxyphenylethylamine was washed with 5 mls of water and dried in vacuum. Yield 0,5 g (83.3%), m.p. 173-174 deg. C. (from alcohol) To the mixture of obtained 0.5 g of amine and 0.45 mls of water was added 0.9 mls of dilute hydrocloric acid (1:1). After removing of water in vacuum 3-methoxy-4,5-dioxyphenylethylamine hydrochloride was obtained. Yield 0.5 g (50,1%), m.p. 198-199 deg. C. (from alcohol). so there is nothing about obtaining bisulfate or doing something with acetate. 4. Yes, everything is like this. but nothing is said about pressure and temperature, so I think it is room temp. |
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Diafrag (ChemLover) 06-01-02 13:27 No 316724 |
I've scanned this article. | Bookmark | ||||||
As i thought, it's quite interesting. it is availible here http://www.chemlover.narod.ru/articles/a |
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