Reaktion #445462

Reaktionsgleichung

1-{(+) 4-[(6,7-dichloro-2-cyclopentyl-2,3-dihydro-2-methyl-1-oxo-1H-inden-5-yl)oxy]butanoyl}imidazole

1-{(+)-4-[(6,7-dichloro-2-cyclopentyl-2,3-dihydro-2-methyl-1-oxo-1H-inden-5-yl)oxy]butanoyl}imidazole

2-hydroxyisobutyric acid

sodium hydride

→

1-carboxy-1-methylethyl (+) 4-[(6,7-dichloro-2-cyclopentyl-2,3-dihydro-2-methyl-1-oxo-1H-inden-5-yl)oxy]butanoate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Einengenthe colorless reaction mixture is concentrated in vacuo at 50° C
2. 2
   SonstigeThe resultant yellow liquid is chromatographed
3. 3
   Wascheneluted with a mixture of methylene chloride, tetrahydrofuran and acetic acid (100/2/1 v.v.v)

Vorschrift

To the solution of 1-{(+) 4-[(6,7-dichloro-2-cyclopentyl-2,3-dihydro-2-methyl-1-oxo-1H-inden-5-yl)oxy]butanoyl}imidazole (0.002 mole) prepared in Step A at 0° C. is added with stirring 2-hydroxyisobutyric acid (0.21 g., 0.002 mole) and a catalytic amount of sodium hydride (10 mg). After stirring overnight at the ambient temperature, the colorless reaction mixture is concentrated in vacuo at 50° C. The resultant yellow liquid is chromatographed using a silica-gel (60 gm) column and eluted with a mixture of methylene chloride, tetrahydrofuran and acetic acid (100/2/1 v.v.v) to give analytically pure 1-carboxy-1-methylethyl (+) 4-[(6,7-dichloro-2-cyclopentyl-2,3-dihydro-2-methyl-1-oxo-1H-inden-5-yl)oxy]butanoate.

Quelle