Reaktion #536367

Reaktionsgleichung

methyl carbamate

2-oxo-4-(hydroxymethylphosphinyl)-butanoic acid

acetic acid

→

objective compound

Ausbeute 56.8%

(Z)-2-methoxycarbonylamino-4-(hydroxymethylphosphinyl)-2-butenoic acid

Ausbeute 56.8%

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.DISSOLUTIONAfter being dissolved
2. 2
   Temperaturby heating
3. 3
   Temperaturthe solution was refluxed with vigorous stirring
4. 4
   Sonstigewas from 106 to 108 deg. C
5. 5
   SonstigeSix hours
6. 6
   FiltrationThe deposited precipitate was filtered
7. 7
   Waschenthe filtrate was washed with acetic acid
8. 8
   WaschenAfter being washed with acetone
9. 9
   Sonstigedried for 5 hours from 40 to 50 deg. C

Vorschrift

16.673 g of methyl carbamate, 0.549 g of p-toluenesulfonic acid monohydrate, and 20.000 g of 2-oxo-4-(hydroxymethylphosphinyl)-butanoic acid were added to 56 mL of acetic acid to be suspended. After being dissolved by heating, 112 mL of toluene was added thereto and then the solution was refluxed with vigorous stirring. The internal temperature of the reaction solution was from 106 to 108 deg. C. Six hours later, dissipation of almost all the raw materials was confirmed by HPLC measurement. At this point, the area ratio of Z form to E form was 81:19. The deposited precipitate was filtered and then the filtrate was washed with acetic acid. After being washed with acetone, dried for 5 hours from 40 to 50 deg. C. under a reduced pressure, 14.966 g of the objective compound was obtained (56.8% yield, Z:E=99.7:0.3).

Quelle