反应详情

10.89 g of 1,1-dimethylguanidine sulfate, 6.4 g of a 50% sodium hydroxide solution and 30 ml tetrahydrofuran are stirred for 2 hrs at RT. 5 g of anhydrous sodium sulfate are added, followed by the dropwise addition of a solution of 2,6-dichlorodichorophenylacetyl chloride (8.94 g) in 16 ml of tetrahydrofuran. The resulting mixture is stirred overnight at RT. The reaction mixture is evaporated to dryness and the residue stirred with 50 ml H2O at RT for 1 hr. The mixture is filtered and the solid washed with H2O and dried in vacuo. The resulting solid is extracted with 50 ml of boiling acetonitrile, filtered while hot, and the filtrate evaporated in vacuo. The resulting white solid is extracted with hot chloroform, filtered and the filtrate evaporated to dryness. The residue is recrystallized from benzene/chloroform. The solvent is removed and the residue dried in vacuo. The resulting material is taken up in ca 100 ml of chloroform, washed with 100 ml H2O and the chloroform layer separated, dried with magnesium sulfate and evaporated to dryness to afford a yellow oil. The yellow oil is taken up in chloroform and the resulting solution brought to pH 2 with methanolic hydrochloric acid. The solution is evaporated to dryness and the residual yellow solid crystallized to afford 4.38 g of tan crystalline solid, M.P. 225.5°-227° C.

1. customThe reaction mixture is evaporated to dryness
2. stirringthe residue stirred with 50 ml H2O at RT for 1 hr
3. filtrationThe mixture is filtered
4. washthe solid washed with H2O
5. customdried in vacuo
6. extractionThe resulting solid is extracted with 50 ml of boiling acetonitrile
7. filtrationfiltered while hot, and the filtrate
8. customevaporated in vacuo
9. extractionThe resulting white solid is extracted with hot chloroform
10. filtrationfiltered
11. customthe filtrate evaporated to dryness
12. customThe residue is recrystallized from benzene/chloroform
13. customThe solvent is removed
14. customthe residue dried in vacuo
15. washwashed with 100 ml H2O
16. customthe chloroform layer separated
17. dry with materialdried with magnesium sulfate
18. customevaporated to dryness
19. customto afford a yellow oil
20. customThe solution is evaporated to dryness
21. customthe residual yellow solid crystallized