Ethanol → ethyl 2-(tert-butoxy)-2-[3-(3,4-dihydro-2H-1-benzopyran-6-yl)-5-phenylthiophen-2-yl]acetate

Participants

Reaction Conditions

Reaction Steps

A solution of ethyl 2-(3-bromo-5-phenylthiophen-2-yl)-2-(tert-butoxy)acetate (10d) (86 mg, 0.22 mmol), 6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)chroman (101 mg, 0.39 mmol) and sodium carbonate (92 mg, 0.87 mmol) in a mixture of toluene (1.26 mL), ethanol (0.6 mL) and water (0.5 mL) was bubbled with nitrogen for 5 minutes. Palladium tetrakis(triphenylphosphine) (12 mg, 0.01 mmol) was added and the reaction mixture was heated at 95° C. overnight. After cooling to room temperature, water (2 mL) was added. The aqueous layer was extracted with toluene (2×8 mL). The organic layers were washed with brine (5 mL), dried over sodium sulfate and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (cyclohexane/ethyl acetate 80/20) to provide the desired product (10e) (80 mg, 0.18 mmol, 82%).

Provenance & Evidence