Reaction #1827

Reaction equation

NaCl

Hydrazine hydrate

KOH

2-[2-oxo-2-(3-thienyl) ethyl]malonic acid

HCl

→

oil

Yield 87.6%

4-(3-thienyl)butyric acid

Yield 87.6%

Solvents

ethylene glycol

Conditions

Workup

1. 1
   TemperatureThis solution was heated
2. 2
   Temperatureat reflux for 6 hours
3. 3
   Otherthe crude reaction mixture
4. 4
   Extractionextracted with ether (3×70 mL)
5. 5
   DryingThe combined organic extracts were dried over Na2SO4
6. 6
   Concentrationconcentrated, in vacuo

Procedure

Hydrazine hydrate (1.3 mL, 1.34 g, 26.8 mmol) was added dropwise to a solution of KOH (3.54 g, 63 mmol) and 2-[2-oxo-2-(3-thienyl) ethyl]malonic acid 8(c) (4.00 g, 17.5 mmol) in ethylene glycol (30 mL). This solution was heated at reflux for 6 hours. After cooling to room temperature, the crude reaction mixture was poured into a mixture of 6N HCl (50 mL) and ice (200 g). This aqueous mixture was saturated with NaCl, then extracted with ether (3×70 mL). The combined organic extracts were dried over Na2SO4 and concentrated, in vacuo, to provide an orange oil (2.61 g) of sufficient purity to be employed in the subsequent reaction without any further purification.

Source