Vitus_Verdegast (Stranger)
08-01-02 07:03
No 339809
      German translators needed here!  Bookmark   

Found this article in an old journal, I know the yields are low but for people that have some tryptophan lying around this is an easy one-pot shot at this desirable AMT/AET precursor, indole-3-carboxaldehyde.

This is the original German text:

Oxydation von Tryptophan zu 3-indolaldehyd.

Ber. Deut. Chem. Gesell 39, 1906, p.2518

oxydation des tryptophans erfolge nach der von Hopkins und Cole gegebenen Vorschrift:  2-3g
substanz wurden in 1L Wasser gelöst und auf dem siedenden wasserbade die fünffache menge
eisenchlorid in 10-procentiger lösung in kleinen portionen zugegossen. Die dunkel gefärbte
 flüssigkeit blieb eine stunde auf dem wasserbade und wurde schlieslich noch eine
 viertelstunde im sieden gehalten. Die erkaltete lösung wurde 3 mal je 15-30 minuten im
schüttelapparat mit viel Aether ausgeschüttelt, die aetherlšsungen gründlich mit wasser
gewaschen und der aether abgedestilliert. die menge des gesammten rückstandes betrug in
meinen versuchen selten mehr als 10 pct. des ausgangsmaterials. Die ausgeschüttelde
lösung wurde durch zusatz von natronlauge vom eisen befreit, der ueberschuss von
natronlauge mit salzsaure neutralisirt, und es wurde von neuem, wie oben angegeben,
oxydirt. Durch dreimalige wiederholung der operation wurden schliesslich ca. 25 pct.
 des tryptophans an oxydationsproduct erhalten. Die von Hopkins und Cole aus der
 alkalisch gemachten lÖsung erhaltene base C12H10N2 konnte ich in keinem meiner
zahlreichen versuche auffinden.
Der aetherrückstand wurde wiederholt aus heissem wasser
umkrystallisirt und so, ein wenig gelb gefärbt, nahezu rein, in rhombischen tafeln vom
schmp. 193¡ erhalten. (ausbeute ca. 15 pct. des tryptophans)  Die letzten spuren farbstoff
 sind schwer zu entfernen. Am besten gelang es, wenn die wässrige lösung mit viel
thierkohle gekocht wurde, wobei fast die ganze substanz in die kohle ging, und die
thierkohle gründlich mit heissem alkohol extrahiert wurde. Der rückstand der alkoholische
lösung, aus wasser umkrystallisirt, liefere farblose, häufig gezackte tafeln vom schmp.
 195¡, dem gleichen, welchen Hopkins und Cole angeben. Die substanz stimmte auch in ihrem
 chemischen verhalten mit der englischen forscher überein.

 0,1709 g Sbst.:  0,4650 g CO2 ;
 0,0758 g H2O

     C9H7NO.  Ber. C 74.48 ; H 4.88
                    Gef. C 74.21 ; H 4.98


Now this is the silly "translation" using AltaVista Babelfish :

Oxidation from Tryptophan to 3-indolaldehyd. 

Ber.  Deut.  Chem. Gessell. 39, 1906, p.2518

The oxidation tryptophans takes place according to the regulation given by Hopkins and Cole:  2-3g substance became in 1L water solved and on the simmering water-bathe the fivefold mixes iron perchloride in 10-procentiger solution in small portions course-poured. 
The darkly colored liquid remained one grants on water-bathes and schlieslich still another one quarter of an hour in to simmer was held. 
The solution cooled off was out-vibrated 3 time per 15-30 minutes in the schuettelapparat with much ether, which ether solutions thoroughly washed with water and the ether abgedestilliert.  those mixes the gesammten arrears amounted to in my tries rarely more than 10 pct. the raw material.  The ausgeschuettelde solution was released by additive of caustic soda solution from the iron, which surplus of caustic soda solution with salt-sour neutralisirt, and it was indicated above, oxydirt by new, as.  By threefold repetition of the operation became finally approx..  25 pct.  keep oxydationsproduct tryptophans on.  The cousin C12H10N2 received from Hopkins and Cole from the alkalinely made solution I knew in none my numerous try find
The ether arrears were umkrystallisirt repeated from hot water and colored a little yellow so, almost purely, in rhombic boards of schmp.  193¡received (exploit approx..  15 pct. tryptophans) the latter keeps in track coloring material is difficult to remove. 

Best it succeeded, if the aqueous solution with many thierkohle were cooked, whereby nearly the whole substance charred in went, and which was extracted thierkohle thoroughly with hot alcohol. 

The arrears of the alcoholic solution, from water umkrystallisirt, supply colorless, frequently serrated boards of schmp.  195¡, which resemble, which Hopkins and Cole indicate.  The substance agreed restrained also in their chemical with the English researchers. 

0.1709 g Sbst.:  0.4650 g CO2;  0.0758 g HÒ

C9H7NO.  Ber.  C 74.48;  H 4,88 Gef. C 74.21;  H 4.98

Could someone help me with this, I'd like to have a decent translation before I start messin' around.

"There are many things under the sun."
08-08-02 08:36
No 343022 is better  Bookmark   

This was translated using, which is somewhat better:

The oxidation of the tryptophans results after the direction given by Hopkins and Cole: 2-3g substance became in 1L water solved and were added on the boiling wasserbade the fivefold quantity of iron chloride in 10-procentiger lösung in little portions.  The darkly colored fluid remained a hour on the wasserbade and became boil held schlieslich another quarter of an hour in that.  The erkaltete solution became 3 once per 15-30 minutes in the schüttelapparat with much ether ausgeschüttelt, that washed ether solutions thoroughly with water and the ether abgedestilliert. the quantity of the gesammten residue amounted to in mine try rarely more than a 10 pct. the exit material.  The ausgeschüttelde solution was freed by addition of soda lye of the iron, the excess of soda lye with salt auras neutralisirt, and it became by new how above indicated, oxydirt.  Through triple repetition of the operation became finally ca.  Receive 25 pct. the tryptophans at oxydationsproduct.  I could would try discover the solutions made by Hopkins and Cole out of the alkalisch received base C12H10N2 in none of my numerous.  The ether residue became repeatedly out of hot water umkrystallisirt and so, a few yellow colored, almost purely, in rhombic chalkboards of the schmp.  Receive 193°.  (Would exploit ca.  15 pct. the tryptophans) the last dyes saved are to be removed heavily.  Best it succeeded if the wässrige solution with much thierkohle was cooked, whereby almost the entire substance went into the coal, and the thierkohle was extracted thoroughly with hot alcohol.  The residue the solution alcoholic, out of water umkrystallisirt, would deliver pale, frequently notched chalkboards of the schmp.  195°, the same which Hopkins and Cole indicate.  The substance agreed retain also in its chemical with the English researchers unanimously.  0,1709 g most self-service. : 0,4650 g CO2; 0,0758 g H2O C9H7NO.  Ber.  C 74.48; H of 4.88 Gef.  C 74.21; H of 4.98


"There are many things under the sun."
08-08-02 08:57
No 343030
      The final translation  Bookmark   

It comes all down to this: Dissolve 3 gr tryptophan in hot water and add with stirring 150 gr 10% FeCl3-sol in small portions. The solution was held on the boiling waterbath for an hour during which the sol. became to a boil. Let it boil another 15 min. ; let cool to RT and extract 3 times with ether using a shaker apparatus. Shake for 15-30 minutes each time. (alternatively, saturate sol with NaCl and extract?)
This was washed with dil. NaOH (to remove solvated iron), water and brine (?), dried and the ether evaporated, to leave a residue, which was recrystallised from hot water repeatedly.
The operation was performed 3 times, so to get 25% of the tryptophan as the oxidation product. Gives yellow rhombic crystals with an mp. of 193°C. (yield 15%)

Well, it's here for the sake of the search engine. I know it gives a shit yield, but this is still usable for people that want to synthesize a small amount of AMT, like SWIM.
Maybe with some tweaking of the procedure the yields could get a bit higher.

"There are many things under the sun."