Tetrahydrofuran → Ethyl 7-(2-amino-4-(tert-butoxycarbonyl)phenoxy)-6,8-dichlorochroman-4-carboxylate

Participants

Reaction Steps

A mixture of ethyl 7-(4-(tert-butoxycarbonyl)-2-nitrophenoxy)-6,8-dichlorochroman-4-carboxylate (61.593 g, 120.22 mmol), THF (500 ml), and saturated NH4Cl solution (500 ml) was purged with Argon for 10 minutes. Zn dust (78.612 g, 1202.2 mmol) was added and the mixture was stirred at ambient temperature for 1 hour under Argon atmosphere. The reaction was slightly exothermic. The mixture was diluted with EtOAc (500 ml) and filtered. The filtered solid was rinsed with EtOAc (250 ml). The filtrate was transferred to a 3 L separatory funnel. The layers were separated and the organic layer was washed with brine (250 ml). The organic layer was dried over MgSO4, filtered, and concentrated. The crude residue was purified on silica gel (EtOAc in hexanes gradient) to provide 45.6 g of the title compound as an oil (79%).

Provenance & Evidence