2-Methyl-3-butyn-2-ol → 5-difluoromethyl-4-{5-(3-hydroxyl-3-methyl-1-butynyl)-2-methylbenzyl}-2-methyl-2,4-dihydro-3H-1,2,4-triazol-3-one

Participants

Reaction Steps

664 mg (2.0 mmol) of 4-(5-bromo-2-methylbenzyl)-5-difluoromethyl-2-methyl-2,4-dihydro-3H-1,2,4-triazol-3-one (Compound 40), 1.00 g (11.9 mmol) of 2-methyl-3-butyn-2-ol, 70.2 mg (0.10 mmol) of PdCl2(PPh3)2, 57.1 mg (0.30 mmol) of copper iodide, 78.7 mg (0.30 mmol) of triphenylphosphine, 1.0 ml of triethylamine and 10 ml of acetonitrile were mixed, and the mixture was heated under reflux for 5 hours in nitrogen atmosphere. After cooling to room temperature, t-butyl methyl ether was added to the reaction solution, and the mixture was filtrated through celite, then, concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (eluant: hexane/ethyl acetate=2/1 (v/v)) to obtain 400 mg of 5-difluoromethyl-4-{5-(3-hydroxyl-3-methyl-1-butynyl)-2-methylbenzyl}-2-methyl-2,4-dihydro-3H-1,2,4-triazol-3-one (Compound 290).

Provenance & Evidence