Methyl 4-aminobenzoate → HCID 86761833, compound

Participants

Reaction Steps

To a mixture of cyclopentyl(5-fluoro-3-methyl-1-benzofuran-2-yl)methanone (1.3 g) synthesized in Example A67(3), methyl 4-aminobenzoate (798 mg), triethylamine (5.88 mL) and dichloromethane (13 mL) was added titanium (IV) chloride (1.0M dichloromethane solution, 6.3 mL) at 0° C., and the mixture was stirred at room temperature for 2 hr under nitrogen atmosphere. Saturated aqueous sodium hydrogen carbonate solution was added to quench the reaction. The solvent was concentrated under reduced pressure, and the residue was extracted with ethyl acetate. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure to give a dark brown solid. To a solution of the obtained solid in tetrahydrofuran (20 mL) were added sodium cyanoborohydride (657 mg) and acetic acid (1.50 mL), and the mixture was stirred at room temperature for 16 hr. Saturated aqueous sodium hydrogen carbonate solution was added to quench the reaction, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (hexane-ethyl acetate 90:10) to give the title compound (1.27 g, 63%) as a yellow amorphous compound.

Provenance & Evidence