175.2 g (666 mmol) of 4-benzyloxybromobenzene was dissolved in 1.4 L dry THF (MS 4 A) under argon. The solution was cooled to −75° C. and a solution of 416 mL 1.6 M butyllithium (666 mmol) in hexane was added during 40 min. After stirring for 1 h a solution of 113 g (555 mmol) (R)-1-(1-phenyl-ethyl)-piperidin-4-one in 400 mL dry THF was added during 1 h at −75° C. The mixture was stirred for another 1 h and, after heating to room temperature, poured into 1.5 L of ice water. The mixture was extracted with 1 L ethyl acetate. The organic phase was washed with 1 L of a half-saturated NaCl solution, dried over Na2SO4 and concentrated to yield 262 g of (R)-4-(4-benzyloxy-phenyl)-1-(1-phenyl-ethyl)-piperidin-4-ol.
