反应详情

A stirred solution of ethyl 3-(1-(isopropylamino)phthalazin-6-yl)-4-methylbenzoate (4 g, 11 mmol) (obtained by method D below) in ethanol/water (4:1) (50 mL) at RT was treated with potassium hydroxide (1 g, 23 mmol). The mixture was warmed to reflux and stirred for 2 h (M+1=322). The mixture was cooled to RT, then concentrated to remove the organic solvent. The mixture was diluted with 1 N aq. sodium hydroxide (20 mL), extracted with ether (2×50 mL). The combined ether extract was washed with 1N aq. sodium hydroxide (20 mL). The combined water layer was neutralized to pH 7 with conc. HCl. The white precipitate was collected and washed with water (20 mL), azotropically dried with toluene and placed under high vacuum to give 3-(1-(isopropylamino)phthalazin-6-yl)-4-methylbenzoic acid as pale yellow solid.

1. temperatureThe mixture was warmed
2. temperatureto reflux
3. concentrationconcentrated
4. customto remove the organic solvent
5. additionThe mixture was diluted with 1 N aq. sodium hydroxide (20 mL)
6. extractionextracted with ether (2×50 mL)
7. extractionThe combined ether extract
8. washwas washed with 1N aq. sodium hydroxide (20 mL)
9. customThe white precipitate was collected
10. washwashed with water (20 mL)
11. dry with materialazotropically dried with toluene