反应详情

A mixture of 5-nitroisatin (5.00 g, 26.0 mmol), 1,3 propandiol (4.76 mL , 65 mmol, 2.5 eq) and p-toluenesulfonic acid mono-hydrate (0.989 g, 5.2 mmol, 0.2 mol %)) in benzene (500 mL) was refluxed with a Dean Stark Trap for 23 hr. The benzene was decanted off and concentrated. The crude product was purified on Biotage KP silica gel eluting with 50/50 petroleum ether/EtOAc to give the title compound as an off white solid (1.78 g, 27% yield). NMR (300 Mz, DMSO-d6): consistent.

1. temperaturewas refluxed with a Dean Stark Trap for 23 hr
2. customThe benzene was decanted off
3. concentrationconcentrated
4. customThe crude product was purified on Biotage KP silica gel eluting with 50/50 petroleum ether/EtOAc