2-Hydroxyisobutyric acid → 1-Carboxy-1-methylethyl [(3,4-dichloro-6,7,8,8a,9,10-hexahydro-6-oxo-8a-propyl-2-phenanthrenyl)oxy]acetate

Participants

Reaction Steps

[(3,4-Dichloro-6,7,8,8a,9,10-hexahydro-6-oxo-8a-propyl-2-phenanthrenyl)oxy]acetic acid (351 mg, 1 mmole) is dissolved in tetrahydrofuran (10 ml) and treated with 1,1'-carbonyldiimidazole (160 mg, 1 mmole) and the mixture stirred at room temperature for an hour. 2-Hydroxy-2-methylpropionic acid (105 mg, 1 mmole) is added and the mixture stirred for 18 hours at room temperature. The solvent is removed by evaporation in vacuo and the residue purified by column chromatography on silica gel using dichloromethane/tetrahydrofuran/acetic acid 100/2/1, v.v.v. to give 1-carboxy-1-methylethyl [(3,4-dichloro-6,7,8,8a,9,10-hexahydro-6-oxo-8a-propyl-2-phenanthrenyl)oxy]acetate.

Provenance & Evidence