Lithium diisopropylamide (56 mL of 1.8M, 100 mmol) was added to a solution of ethyl cyclohexylacetate (16.0 g, 100 mmol) in 50 mL tetrahydrofuran at -40° C. and the solution stirred for 0.5 hour. After further cooling to -70° C., 4,4'-difluorobenzophenone (10.9 g, 50 mmol) was added and the solution stirred for 1 hour at -70° C. and then allowed to warm to -10° C. during the next 2 hrs. The reaction was quenched with 2N hydrochloric acid and extracted with diethyl ether. The extracts were dried with magnesium sulfate and concentrated in vacuo. The residue was crystallized from hexane to give 158 g of the title compound; m.p. =118°-119° C.
