Diphenylacetaldehyde → (R)-1-(2-((2,2-Diphenylethenyl)oxy)ethyl)-3-piperidinecarboxylic acid ethyl ester

Participants

Reaction Steps

Diphenylacetaldehyde (4.9 g, 0.025 mole) was added dropwise to a mixture of sodium hydride (1.5 g, 0.05 mole, 80% oil dispersion) and dry toluene (25 ml) at 0° C. This mixture was stirred at room temperature for 0.5 h, heated to 50° C. and allowed to cool to room temperature. The above (R)-1-(2-bromoethyl)nipecotic acid ethyl ester hydrobromide (8.6 g, 0.025 mole) was added portionwise whilst the temperature was kept below 30° C. with an ice-water bath. After being stirred for 1 h the reaction mixture was filtered, and the filtrate was evaporated to dryness. Flash chromatography of the residue on silica gel (200 g) using a mixture of heptane and tetrahydrofuran (4/1) as eluent provided the title compound (6.6 g, 69%) as an oil. Tlc: rf 0.24 (SiO2 ; heptane/THF 7/3).

Provenance & Evidence