A solution of N-(diphenylmethylene) aminoacetonitrile (5.14 g, 23.4 mmol) in DCM (12 mL) is treated with (R)-4-[4-(3-bromo-propyl)-phenoxymethyl]-2,2-dimethyl-[1,3]dioxolane (8.1 g, 24 mmol) in DCM (12 mL) and cooled to 0° C. Aqueous NaOH (20 mL of a 48% aqueous solution) is added followed by benzyltriethylammonium chloride (530 mg, 2.4 mmol) and the resulting mixture is allowed to warm to RT. After stirring vigorously for 4 h the mixture is diluted with DCM (100 mL) and the aqueous portion is removed. The organic layer is washed with water (2×50 mL), brine then dried (MgSO4), filtered and concentrated in vacuo. The crude product is purified by flash chromatography (SiO2, iso-hexane:diethyl ether) to yield the title compound as yellow oil as a mixture of diastereoisomers.
