反应详情

Methyl 7-(4-(tert-Butoxycarbonyl)phenoxy)-6-cyanochroman-4-carboxylate (18.5 g, 45.185 mmol) was dissolved in dichloromethane (200 mL). Trifluoroacetic acid (50 mL) was added and the mixture was stirred at ambient temperature for 1.5 hours, and then concentrated under reduced pressure to provide a crude solid. The solid was dissolved in EtOAc (200 ml), and hexanes (600 ml) were added with stirring. White solid was crashed out and was collected by filtration to provide 13.11 g of the desired compound as white solid (81.9%). The mother liquor was concentrated and the residue was dissolved in EtOAc (25 ml). Hexanes (100 ml) were added with stirring and a white solid was crashed out and was collected by filtration to provide an additional 1.14 g of the desired compound.

1. concentrationconcentrated under reduced pressure
2. customto provide a crude solid
3. stirringwith stirring
4. filtrationwas collected by filtration