Nitric Acid → 4-Nitroestrone

Participants

Reaction Conditions

Reaction Steps

To a suspension of estrone (11, 8.11 g, 30 mmol) in acetic acid (250 mL) was heated to 120° C. and cooled to 50° C. To the reaction mixture was added 70% nitric acid (2.27 mL, 36 nunol, in an acetic acid (8.0 mL) solution) at 50° C., and stirred for 20 h at room temperature. The precipitate was filtered and washed with acetic acid, H2O, Et2O to afford 1.18 g of 76a (13% yield) mp: >250° C. To the filtrate was added H2O; it was then extracted with Et2O. The combined organic layers were washed with H2O, saturated aqueous NaCl, and then dried (Na2SO4). The desiccant was filtered and the solvent was evaporated at reduced pressure. The residue was purified by column chromatography (silica gel) using n-hexane:EtOAc (2:1, v/v) to afford 3.25 g of 76b (34% yield) mp: 178-180° C.

Provenance & Evidence