Boron trifluoride → N-((S)-2-((3S,5R,6S)-3-allyl-5-(3-chlorophenyl)-6-(4-chlorophenyl)-3-(hydroxymethyl)-2-oxopiperidin-1-yl)butyl)-N-methylcyclopropanesulfonamide

Participants

Reaction Steps

A solution of N-((S)-2-((3S,5R,6S)-3-allyl-5-(3-chlorophenyl)-6-(4-chlorophenyl)-2-oxo-3-((2-(trimethylsilyl)ethoxy)methyl)piperidin-1-yl)butyl)-N-methylcyclopropanesulfonamide (Example 414, Step D, 1.85 g, 2.72 mmol) in DCM was treated with boron trifluoride (diethyl etherate, purified, redistilled, 0.672 ml, 5.44 mmol) for 2 hours. The reaction mixture was diluted with DCM and washed with satd NaCl. The organic extract was dried over Na2SO4, filtered and concentrated in vacuo to give the crude material as an oil. The product was purified by chromatography on a RediSep® pre-packed silica gel column (Teledyne Isco, Lincoln, Nebr.) (12 g), eluting with a gradient of 0% to 80% EtOAc in hexane, to provide the intermediate N-((S)-2-((3S,5R,6S)-3-allyl-5-(3-chlorophenyl)-6-(4-chlorophenyl)-3-(hydroxymethyl)-2-oxopiperidin-1-yl)butyl)-N-methylcyclopropanesulfonamide (1.55 g, 2.67 mmol, 98% yield) as an oil which was used directly in the next reaction.

Provenance & Evidence