Triethylborane → HCID 9908822, compound

Participants

Reaction Steps

To an ice cooled solution of 1-(4-methoxy-phenyl)-5-(4-methylsulfonyl-phenyl)-3-trifluoromethyl-1H-1,2,4-triazole (10 g, 25.19 mmol) in THF (100 ml) was added dropwise a 2 M solution of n-butylmagnesium chloride in THF (21 ml, 42 mmol). Then the reaction mixture was stirred at room temperature for 3 h. The reaction mixture was cooled to 0° C., a 1 M solution of triethylborane in THF (70 ml, 70 mmol) was added dropwise and the reaction mixture was refluxed for 18 h. After cooling, a solution of hydroxylamine-O-sulfonic acid (12 g, 106 mmol) and sodium acetate (17.38 g, 210 mmol) in H2O (140 ml) was added dropwise while maintaining the temperature below 15° C. Then the reaction mixture was stirred at room temperature for 2 h, the residue was extracted with ethyl acetate (2×100 ml), the organic layer was washed with saturated brine, dried over sodium sulfate and evaporated under vacuum. The resulting residue was chromatographed on silica gel using a 99/1 then 98/2 mixture of methylene chloride/methanol as the eluent, then recrystallized from ethanol to give a beige solid (2.5 g, 25%).

Provenance & Evidence