Triethylamine → 2-Fluoro-5-((3-oxoisobenzofuran-1(3H)-ylidene)methyl)benzonitrile

Participants

Reaction Conditions

Reaction Steps

To a mixture of (3-oxo-1,3-dihydro-isobenzofuran-1-yl)phosphonic acid dimethyl ester (G) in tetrahydrofuran and 2-fluoro-5-formylbenzonitrile (F) in tetrahydrofuran was added triethylamine drop-wise over 25 min, with the temperature kept below 15° C. The reaction mixture was warmed slowly to 20° C. over 1 hour and concentrated in vacuo. The white residue was slurried in water or 30 minutes, filtered, washed with water, hexane and ether, and dried to yield 2-fluoro-5-(3-oxo-3H-isobenzofuran-1-ylidenemethyl)benzonitrile (E) as a 50:50 mixture of E and Z isomers (yield: 96%).

Provenance & Evidence