Hydrochloric Acid → 5-[4-(1-Methylbenzimidazol-2-ylmethoxy)benzyl]thiazolidine-2,4-dione

HRID 482518Notes

Reaction equation

HRID 482518 reaction equation
[CH3:1][NH:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[NH2:9].C(O[C:13]([CH2:15][O:16][C:17]1[CH:30]=[CH:29][C:20]([CH2:21][CH:22]2[S:26][C:25](=[O:27])[NH:24][C:23]2=[O:28])=[CH:19][CH:18]=1)=O)C.Cl.C(=O)([O-])O.[Na+]>O1CCCC1.O.O1CCOCC1>[CH3:1][N:2]1[C:3]2[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=2[N:9]=[C:13]1[CH2:15][O:16][C:17]1[CH:18]=[CH:19][C:20]([CH2:21][CH:22]2[S:26][C:25](=[O:27])[NH:24][C:23]2=[O:28])=[CH:29][CH:30]=1

Participants

8

Reactant 4

HCID 313Hydrochloric AcidHCID 78498N-Methyl-o-phenylenediamineHCID 516892Sodium BicarbonateHCID 10852377Ethyl 2-[4-[(2,4-dioxo-1,3-thiazolidin-5-yl)methyl]phenoxy]acetate

Product 1

HCID 97993515-[4-(1-Methylbenzimidazol-2-ylmethoxy)benzyl]thiazolidine-2,4-dioneYield 43.2%

Reagents, catalysts & solvents 3

HCID 962WaterSolvent2×HCID 8028TetrahydrofuranSolventHCID 312751,4-DioxaneSolvent

Procedure

A mixture of 1.0 g of N-methyl-1,2-phenylenediamine, 3.8 g of 5-[4-(ethoxycarbonylmethoxy)benzyl]thiazolidine-2,4-dione [prepared as described in step (d) above], 20 ml of concentrated aqueous hydrochloric acid, 10 ml of 1,4-dioxane and 10 ml of water was heated under reflux for 5 hours. At the end of this time, the insoluble materials which had precipitated from the reaction mixture were collected by filtration and the precipitate thus obtained was dissolved in tetrahydrofuran. Water was then added to the solution. The resulting aqueous mixture was neutralized by adding sodium hydrogencarbonate and then extracted with ethyl acetate. The extract was washed with an aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. The solvent was then removed by evaporation under reduced pressure, and the resulting residue was purified by column chromatography through silica gel using ethyl acetate and then ethanol as the eluent. The product was then recrystallized twice from a mixture of tetrahydrofuran and ethyl acetate, to give 1.3 g of the title compound, melting at 230°-231° C.

Workup

  1. temperaturewas heated
  2. temperatureunder reflux for 5 hours
  3. customAt the end of this time, the insoluble materials which had precipitated from the reaction mixture
  4. filtrationwere collected by filtration
  5. customthe precipitate thus obtained
  6. extractionextracted with ethyl acetate
  7. washThe extract was washed with an aqueous solution of sodium chloride
  8. dry with materialdried over anhydrous sodium sulfate
  9. customThe solvent was then removed by evaporation under reduced pressure
  10. customthe resulting residue was purified by column chromatography through silica gel
  11. customThe product was then recrystallized twice from a mixture of tetrahydrofuran and ethyl acetate

Sources & evidence

ORD record
ord-51d4ab37791b4704bbe70b9a86b5bebb
Source dataset
uspto-grants-1998_08
Patent number
US05798375

Reaction notes

Loading…