2,2-Dimethoxypropane → (3R,5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-3-((2,2-dimethyl-1,3-dioxolan-4-yl)methyl)-3-methylpiperidin-2-one

Participants

Reaction Steps

To a solution of (3R,5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-3-(2,3-dihydroxypropyl)-3-methylpiperidin-2-one (Example 102, Step A) (4.900 g, 12.00 mmol) and 2,2-dimethoxypropane (14.76 mL, 120 mmol) in N,N-dimethylformamide (34 mL) at room temperature was added CSA (0.279 g, 1.200 mmol) and the reaction mixture was allowed to stir for 1 hr at room temperature. The reaction was quenched with sodium bicarbonate (100 mL) and EtOAc (100 mL). The layers were separated and the organic layer was washed three times with sat. sodium carbonate (100 mL). The aqueous layers were combined and were extracted with EtOAc (200 mL). The organic layers were combined, washed with sat. aq. NaCl solution, dried with sodium sulfate, filtered, and concentrated under reduced pressure to provide the title compound.

Provenance & Evidence