Acetyl chloride → HCID 91507122, compound

Participants

Reaction Steps

To a solution containing 1 equivalent of (3EZ,5S)-1-([1,1′-biphenyl]-4-ylcarbonyl)-5-[5-(1-piperazinylmethyl)-1,2,4-oxadiazol-3-yl]-3-pyrrolidinone O-methyloxime (Example 48) in dry DCM at 0° C. were added 1.5 equivalent of triethyl amine and 1 equivalent of acetyl chloride. The reaction mixture was stirred at this temperature for 30 minutes and then hydrolyzed with ice. The reaction was then made basic with a sodium carbonate solution (10%) and extracted with DCM. The organic phase was dried with magnesium sulfate and solvent removal afforded a residue which was purified by flash-chromatography to give the expected product, (3EZ,5S)-5-{5-[(4-acetyl-1-piperazinyl)methyl]-1,2,4-oxadiazol-3-yl}-1-([1,1′-biphenyl]-4-ylcarbonyl)-3-pyrrolidinone O-methyloxime as a mixture of E-/Z-isomers, in 70% yield (94.4% purity by HPLC). The pure Z-isomer could be separated by flash-chromatography using cyclohexane/ethylacetate (1/1) as eluent, and was obtained in 40% yield (98.0% purity by HPLC).

Provenance & Evidence