Sodium Hydroxide → HCID 19025448, compound

Participants

Reaction Steps

Under a dry nitrogen atmosphere 23.8 ml of a 1.55M solution of n-butyllithium in hexane was added dropwise to a stirred solution of 15.8 g (0.0443 mole) of methyltriphenylphosphonium bromide in 300 ml of dry tetrahydrofuran. This mixture was stirred at room temperature for 2.5 hours, and a solution of 11.1 g of the oil from Step B in 50 ml of tetrahydrofuran was added dropwise. After complete addition, the reaction mixture was heated at reflux for 2.5 hours. The mixture was cooled to room temperature and was poured into 300 ml of an aqueous, 2N sodium hydroxide solution. This mixture was extracted with 300 ml of diethyl ether. The organic extract was dried over anhydrous magnesium sulfate and was filtered. The filtrate was evaporated under reduced pressure, leaving a residue. This residue was purified by column chromatography on silica gel eluting with ethyl acetate: n-heptane (25:75) to yield 3.7 g of 3-trifluoromethyl-4,5-dihydro-1-methyl-4-[3-(1-methylethenyl)phenyl]-1,2,4-triazol-5(1H)-thione as a solid, mp 64°-66° C., Compound 27 of Table 1.

Provenance & Evidence