Diisopropylethylamine → 5-[(1R)-2-{4-[2-(1,1-dioxido-1-benzothiophen-5-yl)-2-oxoethyl]piperazin-1-yl}-1-hydroxyethyl]-4-methyl-2-benzofuran-1 (3H)-one

Participants

Reaction Steps

To a solution of 2-bromo-1-(1,1-dioxido-1-benzothiophen-5-yl)ethanone (50 mg, 0.17 mmol) in 1.0 mL THF and 5-[(1R)-1-hydroxy-2-(piperazin-1-yl)ethyl]-4-methyl-2-benzofuran-1(3H)-one hydrochloride (INTERMEDIATE 12) (61 mg, 0.17 mmol) was added N,N-diisopropylethylamine (0.70 mmol, 120 μL) and allowed to stir at ambient temperature for 2 hours. The reaction was quenched by the addition of water and extracted three times with ethyl acetate (10 mL). The combined organic layers were then dried over sodium sulfate, filtered and concentrated in vacuo. The crude residue was purified via MPLC (10% DCM/MeOH) to afford 5-[(1R)-2-{4-[2-(1,1-dioxido-1-benzothiophen-5-yl)-2-oxoethyl]piperazin-1-yl}-1-hydroxyethyl]-4-methyl-2-benzofuran-1 (3H)-one.

Provenance & Evidence