Estradiol → 3-O-Benzyl Estradiol

Participants

Reaction Steps

A solution of 3,17β-dihydroxyestra-1,3,5(10)-triene (4.73 g, 17.4 mmol) in DMF (10 mL) was added slowly to a stirred and cooled mixture of 60% NaH (1.1 g, 27.5 mmol) in DMF (10 mL). After addition was complete, the cooling bath was removed and the mixture stirred at room temperature for 1 hour until all of the NaH had reacted. Benzyl bromide (2.9 mL, 27.8 mmol) was added in a stream and the solution stirred at room temperature for 20 hours. After concentrating under reduced pressure, the residue was partitioned between EtOAc and 10% citric acid. The aqueous layer was extracted with EtOAc again and the organic extracts combined, washed with saturated NaHCO3 solution, dried (Na2SO4), filtered and concentrated. The residue was triturated with Et2O-hexane to give 5.38 g (85%) of the above-titled product, mp=97°-100°.

Provenance & Evidence