Phthalide → HCID 13934850, compound

Participants

Reaction Steps

To a solution of 2.24 g. (54.3 mmoles) of sodium hydroxide in 450 ml. of methanol was added 9.63 g. (54.3 mmoles) of 1-ethyl-5-hydroxyoxindole and the resulting solution concentrated in vacuo to dryness at 65° C. The residual sodium salt was mixed with 10.7 g. (79.8 mmoles) of phthalide and the mixture heated one hour at 185° C. An additional 4.0 g. (29.9 mmoles) of phthalide was added and the heating continued at 220° C. for 20 minutes. The reaction was cooled, the solids washed with diethyl ether and the remaining solids partitioned between 1N hydrochloric acid and diethyl ether. The organic phase was separated and extracted with a saturated sodium bicarbonate solution. The bicarbonate solution was separated, acidified with 4N hydrochloric acid and extracted with diethyl ether. The ether layer was separated, dried over magnesium sulfate and concentrated to give a solid. Recrystallization from methanol gave 4.0 g. (24% yield) of the desired product, m.p. 180° -181° C.

Provenance & Evidence