Diethyl Ether → 4-Dimethylamino-4-(thiophen-2-yl)-1-(5-(triethylsilyl)pent-4-inyl)cyclohexanol

Participants

Reaction Steps

In a heated apparatus a 1.7 M solution of tert-butyl lithium in pentane (22.3 mL, 37.9 mmol) was slowly added in drops to a solution of triethyl-(5-iodopent-1-inyl)silane (5.64 g, 18.9 mmol) in absolute diethyl ether (50 mL) at an inside temperature of −70° C. to −75° C. with argon. After 120 min at this temperature a solution of 4-dimethylamino-4-(thiophen-2-yl)cyclohexane (4.22 g, 18.9 mmol) in absolute diethyl ether (100 mL) was slowly added in drops and subsequently stirred for 30 min. The reaction solution was then heated to room temperature and mixed with saturated ammonium chloride solution (100 mL). The phases were separated and the aqueous phase extracted with diethyl ether (3×50 mL). The combined organic phases were washed with saturated sodium chloride solution (50 mL), dried with sodium sulphate and concentrated to low volume in a vacuum. The residue (7.02 g) was purified by means of flash chromatography (100 g, 20×4.0 cm) with cyclohexane /ethyl acetate (2:1).

Provenance & Evidence