Trifluoroacetic acid → 3-(3-Cyclopentyloxy-4-methoxyphenyl)tetrahydrothiophene

Participants

Reaction Steps

A solution of 3-(3-cyclopentyloxy-4-methoxyphenyl)-3-hydroxytetrahydrothiophene (2.94 g; which is prepared as described in Example 14) and triethylsilane (2.7 mL) in dichloromethane (30 mL) under a nitrogen atmosphere is treated with trifluoroacetic acid (2.3 mL) during 15 minutes. The mixture is stirred for 3.5 hours and then it is allowed to stand for 2 days. The mixture is diluted with dichloromethane (150 mL) and the solution is washed with saturated aqueous sodium bicarbonate solution (2×25 mL), brine (2×25 mL) and water (2×25 mL). The solution is dried over magnesium sulphate, the solvent is removed and the oily residue is subjected to flash chromatography, using a mixture of pentane and ethyl acetate (19:1 v/v) as eluent, to give 3-(3-cyclopentyloxy-4-methoxyphenyl)tetrahydrothiophene (1.34 g) in the form of a pale yellow oil.

Provenance & Evidence