A mixture of the zinc-copper couple, prepared as described above, (48 gm.) and methylene iodide (37.5 gm.) in tetrahydrofuran (300 ml.) is heated under reflux in a nitrogen atmosphere for an hour. Ethyl [(5,6-dichloro-3-oxo-9a-vinyl-1,2,9,9a-tetrahydro-3H-fluoren-7-yl)oxy]-acetate (8.2 gm., 0.02 mole) is added to the cooled mixture and stirring continued at 25° C. for 24 hours. The mixture is diluted with toluene (200 ml.), filtered and the filtrate is washed successively with saturated aqueous solutions of ammonium chloride and sodium bicarbonate and then with water. The organic lager is dried over anhydrous magnesium sulfate and the solvent removed using a rotary evaporator at reduced pressure. The residue is purified by column chromatography using a silica-gel column to give ethyl [(5,6-dichloro-9a-cyclopropyl-3-oxo-1,2,9,9a-tetrahydro-3H-fluoren-7-yl)oxy]-acetate.
