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

HRID 240279Notes

Reaction equation

HRID 240279 reaction equation
CO[Na].[Na].[Br:5][C:6]1[CH:23]=[CH:22][C:21]([F:24])=[CH:20][C:7]=1[CH2:8][NH:9][C:10]([NH:12][N:13]=[C:14]([CH3:19])[C:15](OC)=[O:16])=[S:11]>CO>[Br:5][C:6]1[CH:23]=[CH:22][C:21]([F:24])=[CH:20][C:7]=1[CH2:8][N:9]1[C:15](=[O:16])[C:14]([CH3:19])=[N:13][NH:12][C:10]1=[S:11]

Participants

5

Reactant 3

HCID 5360545SodiumHCID 86654852Methyl 2-(2-(2-bromo-5-fluorobenzylcarbamothioyl)hydrazono)propanoateHCID 178418582HCID 178418582, compound

Product 1

HCID 583285434-(2-bromo-5-fluorobenzyl)-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Procedure

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).

Workup

  1. temperatureThe mixture was heated
  2. temperatureat reflux for 22 h
  3. customMost of the solvent was evaporated
  4. additionThe residue was diluted with water (100 mL)
  5. extractionextracted with EtOAc (50 mL×2)
  6. washThe extracts were washed with brine
  7. dry with materialdried over MgSO4
  8. concentrationconcentrated
  9. customto give a mixture which
  10. customwas separated by silica gel column
  11. washeluted with 20-30% ethyl acetate in petroleum ether

Sources & evidence

ORD record
ord-0c5f11421ef24b02ad61e10be4baacc4
Source dataset
uspto-grants-2014_02
Patent number
US08648073B2

Reaction notes

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