(4-{(R)-2-[(E)-4-(3-Chlorophenyl)-3-oxo-but-1-enyl]-6-oxo-piperidin-1-yl}-but-2-ynyloxy)-acetic acid methyl ester → (4-{(R)-2-[4-(3-Chlorophenyl)-3-oxo-butyl]-6-oxo-piperidin-1-yl}-but-2-ynyloxy)-acetic acid methyl ester

Participants

Reaction Steps

A solution of (4-{(R)-2-[(E)-4-(3-chlorophenyl)-3-oxo-but-1-enyl]-6-oxo-piperidin-1-yl}-but-2-ynyloxy)-acetic acid methyl ester (35 mg, 0.084 mmol) in toluene (2 mL) was added via cannula to a round-bottomed flask containing hydrido(triphenylphosphine)copper(I) hexamer (164 mg, 0.084 mmol) at −40° C. under nitrogen. The reaction was allowed to warm to rt and stirred for 3 h. The reaction was quenched with NH4OH/NH4Cl (1:1, 5 mL) and extracted with EtOAc (3×7 mL). The combined extracts were dried (MgSO4), filtered and concentrated in vacuo. Purification of the residue by flash column chromatography on silica gel (20%→50% EtOAc/CH2Cl2, gradient) followed by preparative thin layer chromatography (silica, 80% EtOAc/CH2Cl2) afforded 12 mg (34%) of the title compound.

Provenance & Evidence