Hydrochloric Acid → dimethyl 4-(6-chloro-3-methyl-4H-1-benzopyran-4-on-2-yl)benzylphosphonate

Temperatur

50 °C

A 39.4 g quantity of 4-[(dimethoxyphosphoryl)methyl]benzoyl chloride was dissolved in 150 ml of dry dichloromethane. Then 150 ml of a pyridine solution containing 27.7 g of 5'-chloro-2'-hydroxypropiophenone was slowly added dropwise to the reaction mixture with stirring under ice-cooling, and the stirring was continued at room temperature for 10 hours. After addition of 150 ml of water, the reaction mixture was extracted with chloroform. The chloroform layer was washed serially with 300 ml of a 10% aqueous HCl solution and 200 ml of water and dried over Glauber's salt. The solvent was distilled off under reduced pressure, and the residue thus obtained was dissolved in 150 ml of pyridine. A 14.0 g quantity of potassium hydroxide was added to the solution with stirring at room temperature, and the mixture was heated at 50° C. with stirring for 2 hours. After addition of 300 ml of a 10% aqueous HCl solution, the reaction mixture was extracted with chloroform. The chloroform layer was washed with 100 ml of water and dried over Glauber's salt. The solvent was distilled off under reduced pressure and the residue was subjected to silica gel column chromatography (eluent: chloroform:ethyl acetate=1:1). The resulting crude crystals were recrystallized from dichloromethane-n-hexane to provide 3.9 g of the title compound as colorless crystals. Table 1 shows the structure and physical property of the compound obtained.

1. additionwas slowly added dropwise to the reaction mixture
2. temperaturecooling
3. extractionthe reaction mixture was extracted with chloroform
4. washThe chloroform layer was washed serially with 300 ml of a 10% aqueous HCl solution and 200 ml of water
5. dry with materialdried over Glauber's salt
6. distillationThe solvent was distilled off under reduced pressure
7. customthe residue thus obtained
8. stirringwith stirring at room temperature
9. stirringwith stirring for 2 hours
10. extractionthe reaction mixture was extracted with chloroform
11. washThe chloroform layer was washed with 100 ml of water
12. dry with materialdried over Glauber's salt
13. distillationThe solvent was distilled off under reduced pressure
14. customThe resulting crude crystals were recrystallized from dichloromethane-n-hexane

ORD-Eintrag

ord-f61a74d1a0484162a5ce9917f38cf0f4

Quelldatensatz

uspto-grants-1996_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05527786