Dabco → Methyl 4-bromo-3-[(dimethylamino)thioxomethoxy]-5-methyl-2-thiophenecarboxylate

HRID 621822Notes

Reaction equation

HRID 621822 reaction equation
[Br:1][C:2]1[C:3]([OH:12])=[C:4]([C:8]([O:10][CH3:11])=[O:9])[S:5][C:6]=1[CH3:7].[CH3:13][N:14]([CH3:18])[C:15](Cl)=[S:16].N12CCN(CC1)CC2>CN(C=O)C>[Br:1][C:2]1[C:3]([O:12][C:15]([N:14]([CH3:18])[CH3:13])=[S:16])=[C:4]([C:8]([O:10][CH3:11])=[O:9])[S:5][C:6]=1[CH3:7]

Participants

5

Reactant 3

HCID 9237DabcoHCID 27871Dimethylthiocarbamoyl chlorideHCID 54697143Methyl 4-bromo-3-hydroxy-5-methylthiophene-2-carboxylate

Product 1

HCID 14154192Methyl 4-bromo-3-[(dimethylamino)thioxomethoxy]-5-methyl-2-thiophenecarboxylateYield 79.8%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

Methyl 4-bromo-3-hydroxy-5-methyl-2-thiophenecarboxylate (2.5 g, 10 mmoles) is stirred under argon in DMF (20 mL). Dimethylthiocarbamyl chloride (2.65 g, 21 mmoles) and 1,4-diazabicyclo[2.2.2]octane (2.4 g, 21 mmoles) are added. The mixture is stirred at room temperature for 2 hours, then at 50° C. for 20 hours, then poured into ice water (200 mL) and extracted twice with toluene. The combined extracts are washed successively with 2N HCl, water, 0.5 M NaHCO3, and water, then dried over MgSO4. Removal of the solvent under reduced pressure, followed by recrystallization from ethyl acetate affords the product (2.7 g); mp 152°-154° C.

Workup

  1. waitat 50° C. for 20 hours
  2. extractionextracted twice with toluene
  3. washThe combined extracts are washed successively with 2N HCl, water, 0.5 M NaHCO3, and water
  4. dry with materialdried over MgSO4
  5. customRemoval of the solvent under reduced pressure
  6. customfollowed by recrystallization from ethyl acetate

Sources & evidence

ORD record
ord-13b3b8de0a20461e83466dd03f886033
Source dataset
uspto-grants-1989_04
Patent number
US04824958

Reaction notes

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