Dimethyl Sulfoxide → 5-({4-[(2S)-2-hydroxy-2-(4-methyl-1-oxo-1,3-dihydro-2-benzofuran-5-yl)ethyl]piperazin-1-yl}acetyl)-4-methyl-2-benzofuran-1(3H)-one

Participants

Reaction Steps

To a solution of oxalyl chloride (71 uL, 0.82 mmol) in DCM (30 mL) was dropped DMSO (120 uL, 1.6 mmol) at −78° C. After stirring the mixture for 10 minutes, a DCM solution of 5,5′-{piperazine-1,4-diylbis [(1S)-1-hydroxyethane-2,1-diyl]}bis(4-methyl-2-benzofuran-1(3H)-one) (380 mg, 0.82 mmol) was added into the reaction. The reaction was stir for another 20 minutes before TEA (570 uL, 4.1 mmol) was added to the reaction mixture. The reaction was then allowed to warm up to RT slowly. TLC analysis showed two new spots right above the SM. LC analysis suggested formation of the mono-ketone as well as the di-ketone. The reaction was diluted with DCM, washed with water, dried over sodium sulfate, and purified by flash chromatography. The title product was collected after removal of solvent.

Provenance & Evidence