2-(2,4-dichlorophenoxymethyl)-3,4-dihydro-2H-pyran → HCID 54156467, Verbindung

To 10 ml of an ethereal solution of 425 mg of α-bromomethyl-2,4-dichlorobenzyl alcohol and 340 mg of 2-(2,4-dichlorophenoxymethyl)-3,4-dihydro-2H-pyran was added a catalytic amount (2 drops) of phosphorus oxytrichloride, and the mixture was stirred at room temperature for 4 days. 3 drops of triethylamine were then added and the solvent was evaporated off under reduced pressure. The residue was purified by column chromatography through silica gel eluted with a 40:2:1 by volume mixture of hexane, benzene and ethyl acetate, to give 681 mg of the isomer of lesser polarity of trans-6-(2,4-dichlorophenoxymethyl)-2-[2-bromo-1-(2,4-dichlorophenyl)ethoxy]tetrahydropyran as colorless crystals melting at 104°-105° C.