반응 #536365

반응 방정식

methyl carbamate

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

acetic acid

→

objective compound

수율 72.2%

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

수율 72.2%

용매

chlorobenzene

반응 조건

후처리

1. 1
   workup.DISSOLUTIONAfter being dissolved
2. 2
   온도by heating
3. 3
   온도the solution was refluxed with vigorous stirring
4. 4
   기타A remaining solution was removed appropriately while the internal temperature of the reaction solution
5. 5
   온도was maintained from 106 to 110 deg. C
6. 6
   workup.ADDITIONby adding chlorobenzene
7. 7
   기타Two hours
8. 8
   기타After removing about 50 mL of the solvent under a reduced pressure
9. 9
   workup.ADDITIONby adding 20 mL of acetic acid
10. 10
    기타The precipitate which was obtained
11. 11
    workup.STIRRINGstirring over-night
12. 12
    여과was filtered
13. 13
    세척the filtrate was washed with acetic acid
14. 14
    세척After being washed with acetone
15. 15
    기타dried for 6 hours from 40 to 50 deg. C

실험 절차

5.835 g of methyl carbamate, 0.275 g of p-toluenesulfonic acid monohydrate and 10.000 g of 2-oxo-4-(hydroxymethylphosphinyl)-butanoic acid were added to 16 mL of acetic acid to be suspended. After being dissolved by heating, 80 mL of chlorobenzene was added thereto and then the solution was refluxed with vigorous stirring. A remaining solution was removed appropriately while the internal temperature of the reaction solution was maintained from 106 to 110 deg. C. under a slightly reduced pressure, followed by adding chlorobenzene, the volume of which was equal to the volume of the removed solution. Two 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 93:7. After removing about 50 mL of the solvent under a reduced pressure, followed by adding 20 mL of acetic acid, and then the resultant was stirred for 1 hour at 80 deg. C. The precipitate which was obtained by cooling the solution gradually to room temperature and stirring over-night, was filtered and then the filtrate was washed with acetic acid. After being washed with acetone, dried for 6 hours from 40 to 50 deg. C. under a reduced pressure, 9.505 g of the objective compound was obtained (72.2% yield, Z:E=99.5:0.5).

출처