Benzyl Alcohol → [8-Bromo-3-(4-chlorophenyl)-2-isopropyl-4-oxo-4H-chromen-7-yl]carbamic acid benzyl ester

Participants

Reaction Steps

A stirred solution of 7-amino-8-bromo-3-(4-chlorophenyl)-2-isopropyl-chromen-4-one (0.242 g, 0.62 mmol) in anhydrous methylene chloride (5 ml) is treated with a 20% solution of phosgene in toluene (0.5 ml). After 3 h, triethylamine (0.12 g, 0.17 ml, 1.24 mmol, 2 eq.) is added, followed by benzyl alcohol (0.067 g, 0.064 ml, 0.62 mmol), and the solution is stirred at room temperature overnight. The solution is diluted with methylene chloride and washed with water. The organic layer is dried (magnesium sulfate) and filtered, and the solvent is removed by evaporation in vacuo. The resulting solid is purified by flash chromatography (cyclohexane/ethyl acetate=9:1) to afford the title compound as a pale yellow solid.

Provenance & Evidence