Dilithium Sulfide → Methyl 2-(difluoromethyl)-4-isobutyl-5-mercapto-6-(trifluoromethyl)-3-pyridinecarboxylate

Participants

Reaction Steps

To a stirred solution of 10.11 g (0.026 mol) of methyl 5-bromo-2-(difluoromethyl)-4-(2-methylpropyl)-6-(trifluoromethyl)-3-pyridinecarboxylate (example 122 of U.S. Pat. No. 5,019,153) in 75 mL dry DMF was added 1.42 g (0.031 mol) of lithium sulfide in one portion and the mixture was stirred overnight at room temperature. The reaction mixture was diluted with 150 mL of 10% HCl solution and extracted with ether (3×100 mL). The combined extracts were washed with water, dried (MgSO4) and evaporated. The residue was purified by kugelrohr distillation (oven temperature 100-110° C., 1.5 torr) to give 7.35 g (83%) of product as a yellow-green oil:

Provenance & Evidence