Ethanol → Carfentrazone-ethyl

Participants

Reaction Steps

To a flask was added 140 g of the 2-chloro-3-{2-chloro-5-[4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl]-4-fluorophenyl}propionic acid, obtained according to the Example 4, 70 g of ethanol, 1.8 g of a concentrated sulfuric acid and 500 g of methyl benzene. The mixture was refluxed for 15 hours to react. The excess ethanol was recovered by distillation. At room temperature the mixture was washed with 200 g of water, with 200 g of a 6% (wt/wt) aqueous solution of sodium carbonate and finally with water. The solvent was completely removed under reduced pressure to give carfentrazone-ethyl as a faint yellow transparent and viscous liquid in a yield of 91% with a purity of 98.2%.

Provenance & Evidence