p-Toluenesulfonic acid → HCID 58932572, compound

Participants

Reaction Steps

To a rapidly and efficiently stirred mixture of 5-{[(2R)-2-(methoxymethyl)pyrrolidin-1-yl]sulfonyl}-1H-indole-2,3-dione (4.21 g, 13.0 mmol) in benzene (300 mL), was added 1,3-propanediol (3.81 mL, 52 mmol, 4 eq) and p-toluenesulfonic acid (0.989 g, 5.2 mmol, 0.4 mole % ) and the reaction was refluxed with a Dean Stark Trap for 4.5 hours under a dry N2 atmosphere. After cooling to room temperature the reaction was washed with sat. aq. NaHCO3 (3×), water (3×), brine (3×), dried over MgSO4, and concentrated. The crude product was purified on Biotage KP silica gel eluting with 50/50 Pet ether/EtOAc to give the title compound as a white solid (1.34 g, 27% yield). NMR (400 MHz, DMSO-d6): consistent; MS: (API-ES−) m/z 381 [M−H]. MS: (API+ES+) m/z 383 [M+H].

Provenance & Evidence