Hydrogen Bromide → 6-Chloro-7-hydroxy-3,4-dihydrocarbostyril

Participants

Reaction Steps

30 Grams of thus obtained 6-chloro-7-methoxy-3,4-dihydrocarbostyril was dispersed in 300 ml of 47% aqueous solution of hydrobromic acid and heated under refluxing condition for 4 hours. After the reaction mixture was cooled, the insoluble matters formed were obtained by filtration, washed with water, dried and recrystallized from methanol-chloroform. 25 Grams of 6-chloro-7-hydroxy-3,4-dihydrocarbostyril having the melting point of 264°-266° C. was obtained as in the form of colorless needle-like crystals.

Provenance & Evidence