Potassium Hydroxide → 7-Benzyloxy-3-(4-chlorophenyl)-8-hydroxy-2-isopropyl-chromen-4-one

Temperatur

50 °C

To a solution of 7-benzyloxy-3-(4-chlorophenyl)-2-isopropyl-4-oxo-4H-chromene-8-carbaldehyde (8.03 g, 18.6 mmol) in CH2Cl2 (200 ml) is added m-chloroperbenzoic acid (9.24 g, 53.5 mmol). The reaction mixture is stirred at 50° C. for 4 h, washed with saturated NaHCO3 solution, dried (MgSO4) and concentrated in vacuo to give a yellow oil. To a solution of the oil in methanol (350 ml) is added aqueous KOH solution (10%, 35 ml), and the mixture is stirred at room temperature overnight. The mixture is concentrated to a ca. 50 ml volume, ice/water is added, and the mixture is acidified with concentrated HCl. A solid is isolated by filtration, washed with water and taken up into CH2Cl2. The CH2Cl2 solution is dried (MgSO4), and the solvent is removed in vacuo to afford a dark brown solid. This is stirred in hot hexane/ethyl acetate and filtered to afford the title compound as a colourless solid. A further crop of the desired product can be isolated from the filtrate by concentrating the hot solution to a quarter of its original volume and allowing it to stand at room temperature.

1. washwashed with saturated NaHCO3 solution
2. dry with materialdried (MgSO4)
3. concentrationconcentrated in vacuo
4. customto give a yellow oil
5. stirringthe mixture is stirred at room temperature overnight
6. concentrationThe mixture is concentrated to a ca. 50 ml volume, ice/water
7. additionis added
8. customA solid is isolated by filtration
9. washwashed with water
10. dry with materialThe CH2Cl2 solution is dried (MgSO4)
11. customthe solvent is removed in vacuo
12. customto afford a dark brown solid
13. filtrationfiltered

ORD-Eintrag

ord-b0ae18a2636d43499671692429290ec2

Quelldatensatz

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07732435B2