반응 #327461

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MeONa

sodium

methyl 2-(2-(2-bromo-5-fluorobenzylcarbamothioyl)hydrazono)propanoate

Methyl 2-(2-(2-bromo-5-fluorobenzylcarbamothioyl)hydrazono)propanoate

→

4-(2-bromo-5-fluorobenzyl)-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one

용매

methanol

methanol

반응 조건

후처리

1. 1
   온도The mixture was heated
2. 2
   온도at reflux for 22 h
3. 3
   기타Most of the solvent was evaporated
4. 4
   workup.ADDITIONThe residue was diluted with water (100 mL)
5. 5
   추출extracted with EtOAc (50 mL×2)
6. 6
   세척The extracts were washed with brine
7. 7
   건조dried over MgSO4
8. 8
   농축concentrated
9. 9
   기타to give a mixture which
10. 10
    기타was separated by silica gel column
11. 11
    세척eluted with 20-30% ethyl acetate in petroleum ether

실험 절차

To a solution of MeONa (0.4 M) in methanol (30 mL), freshly prepared from sodium (273 mg, 11.88 mmol) and dry methanol (30 mL), was added methyl 2-(2-(2-bromo-5-fluorobenzylcarbamothioyl)hydrazono)propanoate (15, 1.434 g, 3.96 mmol). The mixture was heated at reflux for 22 h. Most of the solvent was evaporated. The residue was diluted with water (100 mL), acidified with 2 N HCl to pH=1˜2, and then extracted with EtOAc (50 mL×2). The extracts were washed with brine, dried over MgSO4, and concentrated to give a mixture which was separated by silica gel column, and eluted with 20-30% ethyl acetate in petroleum ether to give 4-(2-bromo-5-fluorobenzyl)-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one (16). MS: m/z, 330 (65%, M+1), 332 (60%, M+23).

출처