Triphenylphosphine → 1,2-Benzisoxazole

Participants

Reaction Conditions

Reaction Steps

Into a 1 L 3-necked round bottom flask purged and maintained with an inert atmosphere of nitrogen, was placed a solution of (E)-2-hydroxybenzaldehyde oxime (3 g, 21.90 mmol) in tetrahydrofuran (300 mL). To the mixture was added PPh3 (6.024 g, 22.99 mmol), while cooling to a temperature of 4° C. This was followed by the addition of a solution of DEAD (4 g, 22.99 mmol) in tetrahydrofuran (150 mL), while cooling to a temperature of 4° C. over a time period of 4 hours. The resulting solution was allowed to react, with stirring, for 1 hour while the temperature was maintained at 4° C. in a bath of H2O/ice. The reaction progress was monitored by TLC (ethyl acetate/petroleum ether=1:2). The mixture was concentrated by evaporation under vacuum using a rotary evaporator. The residue was purified by eluting through a column with a 1:100 ethyl acetate/petroleum ether solvent system. This resulted in 1.8 g (66%) of benzo[d]isoxazole as yellow oil.

Provenance & Evidence