GC_MS (Hive Bee) 11-20-02 12:56 No 381544 |
Hexamethylenetetramine: a review (Rated as: excellent) |
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SWiM was doing some research yesterday in order to find a new and convenient synthesis of PEA and amphetamine analogues. In a very large book describing a zillion possibilities to obtain aromatic aldehydes (SWiM didn't write down the name... It was German, can't give any more details. Shoot me ), he found a (zillion)^2 references to possibly interesting articles. Since SWiM would be banned from this Place if he posted all references (overflow ), he presents you one of the more interesting articles: N Blazevic, D Kolbah, B Belin, V Sunjic, F Kajfez. Hexamethylenetetramine, a versatile reagent in organic synthesis. Synthesis :3 (1979) 161-176. Here are some notes/remarks/theoretical possibilities SWiM found when reading the article: 1. Delépine reaction The Delépine reaction is the conversion of alkyl halides to primary amines: R1R2-CH-X --> R1R2-CH-NH2. Secondary amines are not expected contaminants. Typical procedure: 1-(alfa-aminoacetyl)-3-hydroxy-4-methoxy There is a detailed page regarding the Delépine reaction on Rh's site. 2. Reactions of oxiranes with hexamethylenetetramine (HMTA) in chloroform The reaction of substituted oxiranes (epoxides) with HMTA is a modification of the Delépine reaction. Reaction of an oxirane with HMTA yields 2-amino-1-hydroxy alcohols, while reacting oxiranes with primary, secondary or tertiary amines yields the isomere 1-amino-2-hydroxy as well.
Ave Hive, synthetisandi te salutant! |
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Cyrax (Hive Bee) 11-20-02 14:01 No 381555 |
Good old Cyrax is interested | Bookmark | ||||||
Ph-C---C + HMTA ---> Ph-CH-CH2-NH2 \ / | O OH Yield: 100% (cf. H J Roth, A Brandau. Arch Pharm 292 (1959) 761 That looks mighty interesting. A post of the procedure would be appreciated very much. Is Arch. Pharm. the same journal as Arch. Pharm. Res.? If it is, I wonder if you could look up a little article for me . |
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pHarmacist (Hive Bee) 11-20-02 14:11 No 381558 |
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wow! 2. Reactions of oxiranes with hexamethylenetetramine (HMTA) in chloroform This is relly what I was looking for, awsome, 4-Me-aminorex, here we come.... "Turn on, Tune in and Drop Out" |
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GC_MS (Hive Bee) 11-20-02 14:24 No 381566 |
On the aminolysis of styroloxides (Rated as: excellent) |
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Here are some fragments from: HJ Roth, A Brandau. Ueber die Aminolyse von Styroloxyd: Darstellung von Phenylaminoaethanolen. Archiv der Pharmazie 292 (1959) 761-777. The uebertranssetzung is by SWiM. He picked some interesting notes from the article, i.e. this is NOT the complete text. 1908 - M Tiffeneau and E Fourneau report quantitive conversion of styreneoxide with dimethylamine to 1-phenyl-2-dimethylamino-ethanol [2]. 1945 - W S Emerson obtained the same product by reacting styreneoxyde with NH3, but in 18% yield. Better yields were obtained (up to 80%) when working with primary and secondary amines to obtain the N-substituted compounds [3]. 1950 - W B Wheatley used iPr-amine and obtained 1-phenyl-2-isopropylamino-ethanol in a 71% yield [4]. 1951 - W Beck converted methyl benzylamine to 1-phenyl-2-methylbenzylamino-ethanol with 83% yield [5]. 1952 - C L Browne and R E Lutz converted styreneoxyde with benzylamine and obtained two isomeres [6]. 1954 - J A Castro converted styreneoxyde with NH3 and reports two isomeres as well: 1-phenyl-2-amino-1-ethanol and 1-phenyl-1-amino-2-ethanol (3.6:1 ratio) [7]. 1956 - U Hoffman, H H Kuhn and H Brugger describe in a patent (Anmeinung D 19814 ???) the synthesis of several aminoalcohols from styreneoxyde using NH3. 1957 - W Ziegenbein and W Franke obtained 1-phenyl-2-N-ethanol-1-lactame by reacting styreneoxyde with lactame [9]. When the aminolysis is applied by reacting styreneoxyde with hexamethylenetetramine (HMTA) and with purine bases, only 1-phenyl-2-amino-1-ethanol derivatives are formed. When NH3 ir benzylamine are used, isomeres are detected:
Ave Hive, synthetisandi te salutant! |
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Cyrax (Hive Bee) 11-20-02 14:34 No 381568 |
Damn, that 's a bummer. | Bookmark | ||||||
Damn, that 's a bummer. I thought the yield would be 100 % but it seems to be 29 %. They probably meant 100 % stereoselectivity ... |
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GC_MS (Hive Bee) 11-20-02 15:18 No 381577 |
grms | Bookmark | ||||||
Damn, that 's a bummer. I thought the yield would be 100 % but it seems to be 29 %. They probably meant 100 % stereoselectivity ... No, but the author wrote things down in such a way that the reaction looks rather fabulous... The reaction consists of 2 steps: 1. formation of the hexaminium chloride 2. formation of the 2-amino-1-ethanol derivative using the hexaminium chloride as precursor. The 100% yield is for step 2 only. So it probably is step 1 that lowers your yield (in this case). Another one: H J Roth. Eine neue Methode zur Herstellung von 1-Amino-2-hydroxy-Verbindungen ohne Bildung von Di-und Tri-(oxyalkyl)-aminen als Nebenprodukte. Arch Pharm 292 (1959) 76-82. (some outtakes):
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Cyrax (Hive Bee) 11-20-02 16:11 No 381596 |
OK, I see. Thanks for the clarification. | Bookmark | ||||||
OK, I see. Thanks for the clarification. The last reaction you posted looks rather dangerous, since there is a phosgene evolution ... phosgene ... yummy |
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Natrix (Hive Bee) 11-20-02 19:11 No 381623 |
phenylethanol amines | Bookmark | ||||||
Hoffmann, Kuhn, Brugger: Verfahren zur Herstellung von Phenyläthanolaminen Patent DE975297 |
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Rhodium (Chief Bee) 11-21-02 20:26 No 381907 |
Hexamethylenetetramine (HMTA, Hexamine) (Rated as: excellent) |
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The article referred to in the post at the top of this thread: Post 381544 (GC_MS: "Hexamethylenetetramine: a review", Chemistry Discourse) Hexamethylenetetramine, a versatile reagent in organic synthesis N Blazevic, D Kolbah, B Belin, V Sunjic, F Kajfez Synthesis, No. 3, pp. 161-176 (1979) (../rhodium/pdf /hexamethylen |
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