Carbamate → HCID 21251132, compound

HRID 342775Notes

Reaction equation

HRID 342775 reaction equation
[Cl:1][C:2]1[C:6]([C:7](=O)N(C)C)=[CH:5][S:4][C:3]=1[CH2:12][C:13]([O-])=O.[CH3:16][O-:17].[Na+].[C:19](=O)([O-])N.[CH3:23][O-:24].[Na+].CO.[Br:28][CH2:29][CH2:30]CBr>CO>[Cl:1][C:2]1[CH:6]=[C:7]([CH2:19][C:16]([O:24][CH3:23])=[O:17])[CH:13]=[CH:12][C:3]=1[S:4][CH2:5][CH2:30][CH2:29][Br:28]

Participants

7

Reactant 5

HCID 276CarbamateHCID 80011,3-DibromopropaneHCID 10942334Sodium MethoxideHCID 23694274Sodium methanolate methanolHCID 86753573HCID 86753573, compound

Product 1

HCID 21251132HCID 21251132, compoundYield 48%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent3×

Procedure

To a solution of 3-chloro-4-dimethylcarbamoyl-thiophenylacetate (85 g, 0.295 mol) in methanol (250 mL) was added 25% NaOMe in methanol (74 mL, 0.34 mol). The reaction was heated to reflux for 2 h. TLC analysis shows residual starting carbamate. Additional NaOMe/MeOH (10 mL) was added and the mixture stirred an additional 30 min at reflux. After cooling to ambient temperature, the thiolate solution was added dropwise to a solution of 1,3-dibromopropane (120 mL, 1.18 mol) in methanol (250 mL). The resulting solution was refluxed for 3 h then cooled to ambient temperature. After standing overnight, the reaction was quenched by pouring into ice water (2 L). After adjusting to pH 1 with conc. HCl (ca. 10 mL), the aqueous was extracted with EtOAc (2 L then 2×1 L). The combined organics were washed with water (2×1 L), brine (1 L), dried over anhyd. MgSO4, filtered, and concentrated. The residue was dissolved in EtOAc/ hexane (1/9) and eluted through a plug of silica gel (70-230 mesh, ca. 2 L, packed in EtOAc/hexane, 1/9). The fractions containing product were combined and evaporated to give title compound (48 g, 48% yield) as an off-white solid.

Workup

  1. temperatureThe reaction was heated
  2. temperatureto reflux for 2 h
  3. temperatureat reflux
  4. temperatureThe resulting solution was refluxed for 3 h
  5. temperaturethen cooled to ambient temperature
  6. waitAfter standing overnight
  7. customthe reaction was quenched
  8. additionby pouring into ice water (2 L)
  9. extractionthe aqueous was extracted with EtOAc (2 L
  10. washThe combined organics were washed with water (2×1 L), brine (1 L)
  11. customdried over anhyd
  12. filtrationMgSO4, filtered
  13. concentrationconcentrated
  14. dissolutionThe residue was dissolved in EtOAc/ hexane (1/9)
  15. washeluted through a plug of silica gel (70-230 mesh, ca. 2 L, packed in EtOAc/hexane, 1/9)
  16. additionThe fractions containing product
  17. customevaporated

Sources & evidence

ORD record
ord-6f4bb188d5ca486b9cf1d7428953cbc8
Source dataset
uspto-grants-1999_01
Patent number
US05859051

Reaction notes

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