Diisopropylethylamine → (3R,9aS)-3-(3-Cyano-4-fluoro-2-methyl-phenyl)-3-hydroxy-hexahydro-pyrazino[2,1-c][1,4]oxazine-8-carboxylic acid tert-butyl ester

Participants

Reaction Steps

Diisopropylethylamine (44.0 mL, 252 mmol) was added to a stirred, room temperature mixture of 72 wt % 3-(2-Bromo-acetyl)-6-fluoro-2-methyl-benzonitrile (69 g, 194 mmol) and (S)-4-N-Boc-2-hydroxymethyl-piperazine (42.0 g, 194 mmol) in THF (1000 mL) and the mixture was stirred at room temperature for 18 h. The reaction was diluted with 1 L EtOAc, washed 2× with 500 mL 10% w/w NaHCO3 aqueous solution, dried over MgSO4, filtered and concentrated. The residue was purified by column chromatography on silica gel (40-80% EtOAc/Hexanes, linear gradient), to give the title compound.

Provenance & Evidence