3,3-Dimethyl-1-butyne → methyl {(2S,3R)-1-[(1S)-4,4-dimethyl-1-(3,3,3-trifluoropropyl)pent-2-yn-1-yl]-2-[4-(trifluoromethyl)phenyl]piperidin-3-yl}acetate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of methyl {(2S,3R)-2-[4-(trifluoromethyl)phenyl]piperidin-3-yl}acetate (2.1 g, 7.0 mmol), 4,4,4-trifluorobutanal (1.76 g, 13.9 mmol) and gold(III) bromide (0.3 g, 0.7 mmol) in water (50 mL) was degassed with nitrogen for 1.5 hours. To this solution was added 3,3-dimethylbut-1-yne (4.3 mL, 34.8 mmol) and the reaction was sealed and heated to 70° C. for 16 hours. The reaction was partitioned between water and ethyl acetate. The organics were dried over sodium sulfate, filtered and evaporated in vacuo. Purification by flash column chromatography (3% ethyl acetate/hexanes) gave methyl {(2S,3R)-1-[(1S)-4,4-dimethyl-1-(3,3,3-trifluoropropyl)pent-2-yn-1-yl]-2-[4-(trifluoromethyl)phenyl]piperidin-3-yl}acetate as a clear oil. LC/MS (EIMS, M+H)=492.1.

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