3,4-dihydro-2H-pyran → HCID 21949789, compound

Participants

Reaction Steps

To a stirred solution of 1-(2-hydroxyethyl)-5-methyl-3-(trifluoromethyl)-1H-pyrazol-4-ol (600 mg, 2.86 mmol; Kenkyu Hokoku—Asahi Garasu Kogyo Gijutsu Shoreikai, 1988, 51, 139-49) in dichloromethane (10 ml) and ethyl acetate (4 ml) was added para-toluenesulphonic acid (27 mg, 0.14 mmol) followed by 3,4-dihydro-2H-pyran (340 μl, 3.7 mmol). The reaction mixture was stirred at room temperature for 3 hours before being concentrated under reduced pressure. The crude product mixture was purified by flash chromatography on silica gel eluting with pentane:ethyl acetate (60:40, by volume) to provide the title compound (560 mg) as white solid.

Provenance & Evidence