Hydrogen Sulfide → Diethyl (3-thienyl)malonate

HRID 1414134Notes

Reaction equation

HRID 1414134 reaction equation
[OH-].[K+].[SH2:3].[CH2:4]([O:6][C:7](=[O:20])[C:8]([C:15]([O:17][CH2:18][CH3:19])=[O:16])=[C:9]([CH2:13]Cl)/[CH:10]=[CH:11]/Cl)[CH3:5]>C(O)C.O>[S:3]1[CH:11]=[CH:10][C:9]([CH:8]([C:15]([O:17][CH2:18][CH3:19])=[O:16])[C:7]([O:6][CH2:4][CH3:5])=[O:20])=[CH:13]1

Participants

6

Reactant 3

HCID 402Hydrogen Sulfide3×HCID 14797Potassium Hydroxide2×HCID 12509451HCID 12509451, compound

Product 1

HCID 3015942Diethyl (3-thienyl)malonateYield 78%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 962WaterSolvent

Procedure

Potassium hydroxide (0.14 g, 2.0 mmol) in ethanol (50 ml) was saturated with hydrogen sulphide at 0° for one hour. To this was added 4-trans ethyl-2-ethoxycarbonyl-5-chloro-3-chloromethylpenta-2,4-dienoate (0.62 g, 2.45 mmol), and addition of hydrogen sulphide was continued for one hour at room temperature. The reaction mixture was stirred for a further four hours. Potassium hydroxide (0.20 g, 2.8 mmol) was added and hydrogen sulphide passed for thirty minutes. The reaction mixture was stirred at room temperature for sixteen hours, diluted with water (50 ml) and extracted with ether (3×50 ml). The extracts were washed with saturated brine, N sodium bicarbonate solution, saturated brine, dried (Na2SO4) and evaporated to give the title compound (78% yield) purified by distillation, b.p. 119°-127°/0.5 mm. δ (CDCl3) 1.27 (6H, t, J 7 Hz, CH3), 4.20 (4H, q, J 7 Hz, OCH2), 4.75 (1H, s, CH), 7.20-7.43 (3H, m, thienyl protons), νmax (film) 1730 cm-1, λmax (ethanol) 234 nm. C11H14O4S requires M, 242.0649. Found M+, 242.0609.

Workup

  1. additionTo this was added
  2. stirringThe reaction mixture was stirred at room temperature for sixteen hours
  3. extractionextracted with ether (3×50 ml)
  4. washThe extracts were washed with saturated brine, N sodium bicarbonate solution, saturated brine
  5. dry with materialdried (Na2SO4)
  6. customevaporated

Sources & evidence

ORD record
ord-04c82d5d7727476a932aae9056f556df
Source dataset
uspto-grants-1981_02
Patent number
US04252976

Reaction notes

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