Sodium triacetoxyborohydride → Phthalide

Participants

Reaction Steps

Dissolved 2-(1-oxo-1,3-dihydro-2-benzofuran-5-yl) propanal (38 mg, 0.2 mmol) in dichloroethane (10 mL) and added 1-(piperazin-1-yl) 2-[4-(1H-tetrazol-1yl)phenyl]ethanone (50.1 mg, 0.162 mmol) followed by sodium triacetoxyborohydride (127 mg, 0.599 mmol) then stirred at room temperature for 16 h. The reaction mixture was washed with saturated NaHCO3 solution, brine, dried and concentrated. Purified by MPLC using a 40 g ISCO Redi-sep column and eluted with 0%-10% methanol/ethyl acetate to yield racemate 5-[1-4-{[4-(1H-tetrazol-1-yl)phenyl]acetyl}piperazin-1-yl)propan-2-yl]-2-benzofuran-1(3H)-one. The isomers were separated on Chiracel OD, 2 cm×25 cm, 10μ column using 45% ethanol: 55% heptane solvent system. The retention times for isomer A was at 42 minutes and for isomer B was at 47 minutes.

Provenance & Evidence