Trifluoroacetic acid → 3-[4-[2-(2-Oxopyrrolidin-1-yl)ethoxy]benzyl]-2-[4-[2-(1-pyrrolidinyl)ethoxy]phenyl]benzo[b]thiophene

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Reaction Steps

2-[4-[2-(1-Pyrrolidinyl)ethoxy]phenyl]benzo[b]thiophen-3-yl 4-[2-(2-oxopyrrolidin-1-yl)ethoxy]phenyl ketone (120 mg) was dissolved in THF/MeOH (3.0/0.3 mL) and treated with lithium borohydride (40 mg) in one portion and allowed to stir at ambient temperature for 4 h. The reaction mixture was diluted with brine (30 mL) and extracted with dichloromethane (20 mL×3). The combined organic layers were dried with sodium sulfate and concentrated in vacuo to give the crude alcohol. This material was dissolved in dichloromethane (3.0 mL), treated with triethylsilane (0.25 mL) and trifluroacetic acid (0.2 mL) sequentially, allowed to stir at ambient temperature for 2 h, and concentrated under reduced pressure. The residue was extracted with -dichloromethane (20 mL×3) from saturated aqueous sodium bicarbonate (30 mL). The combined organic layers were dried with sodium sulfate and concentrated. Chromatography with Et3N:MeOH:EtOAc (5:5:90) afforded the title compound (27 mg).

Provenance & Evidence