4,4'-Dichlorobenzophenone → 6,6-Di(p-chlorophenyl)fulvene

Participants

Reaction Conditions

Reaction Steps

A reaction vessel equipped with a dropping funnel was charged with 40 ml of dehydrated tetrahydrofuran and 2.15 ml (25.9 mmol) of cyclopentadiene under a nitrogen atmosphere. Then, 18.0 mL (28.5 mmol) of a 1.58 mol/L hexane solution of n-butyllithium was slowly added dropwise while cooling this solution to 0° C., and the mixture was stirred. Subsequently, the dropping funnel was charged with a solution prepared by dissolving 5.00 g (19.9 mmol) of 4,4′-dichlorobenzophenone in 30 ml of dehydrated tetrahydrofuran was placed in. The solution was slowly added dropwise while cooling to −0° C. Thereafter, the mixture was left to stand and the temperature thereof was returned to room temperature. The mixture was then stirred for one day. This reaction solution was subjected to extraction with diethyl ether. The organic layer was washed with 1 N hydrochloric acid, a saturated aqueous solution of sodium hydrogen carbonate and saturated brine. The organic phase collected by separation was dried over anhydrous magnesium sulfate. Subsequently, magnesium sulfate was separated by filtration, and the filtrate was subjected to distillation under reduced pressure with use of a rotary evaporator to remove the solvent. The residue was purified by using a silica gel column to obtain a target product (yield 3.37 g (57%)). The target product was identified by 1H-NMR.

Provenance & Evidence