Reaction #5363

Reaction equation

thiotetronic acid

triethylamine

1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride

petroselinic acid

HCl

→

4-hydroxy-3-[(Z)-1-oxo-6-octadecenyl]-2(5H)-thiophenone

Yield 21.4%

Solvents

dimethylformamide

Conditions

Workup

1. 1
   Extractionextracted three times with diethyl ether
2. 2
   WashThe combined organic layers are washed with brine
3. 3
   Dryingdried over Na2SO4
4. 4
   Filtrationfiltered
5. 5
   Concentrationconcentrated in vacuo
6. 6
   Washeluting with 100% ethyl acetate

Procedure

To a stirring solution of 1.71 g (14.7 mmol) of thiotetronic acid in 20 mL of dimethylformamide is added 2.22 mL (15.9 mmol) of triethylamine and 592 mg (4.85 mmol) of 4-dimethylaminopyridine at 0° C. Next, 3.38 g (17.6 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 5.0 g (17.7 mmol) of petroselinic acid are added and the reaction mixture is stirred overnight at room temperature. The reaction is acidified with 1.0N HCl and extracted three times with diethyl ether. The combined organic layers are washed with brine, dried over Na2SO4, filtered, and concentrated in vacuo. The residue is subjected to HPLC chromatography (2 inch Dynamax silica gel column, 25 mL/min) eluting with 100% ethyl acetate to give 1.2 g (21%) of 4-hydroxy-3-[(Z)-1-oxo-6-octadecenyl]-2(5H)-thiophenone as an oil.

Source