Reaktion #42755

Reaktionsgleichung

triethylamine

7-amino-8-bromo-3-(4-chlorophenyl)-2-isopropyl-chromen-4-one

phosgene

benzyl alcohol

→

title compound

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

Lösungsmittel

methylene chloride

methylene chloride

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Waschenwashed with water
2. 2
   TrocknenThe organic layer is dried (magnesium sulfate)
3. 3
   Filtrationfiltered
4. 4
   Sonstigethe solvent is removed by evaporation in vacuo
5. 5
   SonstigeThe resulting solid is purified by flash chromatography (cyclohexane/ethyl acetate=9:1)

Vorschrift

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.

Quelle